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Accommodating intraocular lenses: a critical review of present and future concepts.

Graefes Arch. Clin. Exp. Ophthalmol., 2007; 473-89

BACKGROUND: Significant efforts have been made to develop lens implants or refilling procedures that restore accommodation. Even with monofocal implants, apparent or pseudoaccommodation may provide the patient with substantial though varying spectacle independence. True pseudophakic accommodation with a change of overall refractive power of the eye may be induced either by an anterior shift or a change in curvature of the lens optic.

MATERIALS AND METHODS: Passive-shift lenses were designed to move forward under ciliary muscle contraction. This is the only accommodative lens type currently marketed (43E/S by Morcher; 1CU by HumanOptics; AT-45 by Eyeonics). The working principle relies on various hypothetical assumptions regarding the mechanism of natural accommodation. Dual-optic lenses were designed to increase the dioptric impact of optic shift. They consist of a mobile front optic and a stationary rear optic which are interconnected with spring-type haptics. With active-shift lens systems the driving force is provided by repulsing mini-magnets. Lens refilling procedures replace the lens content by an elastic material and provide accommodation by an increase of surface curvature.

RESULTS: Findings with passive-shift lenses have been contradictory. While uncorrected reading vision results were initially reported to be favorable with the 1CU, and excellent with the AT-45 lens, distant-corrected near vision did not exceed that with standard monofocal lenses in later studies. Mean axial shift from laser interferometric measurements under stimulation with pilocarpine showed a moderate anterior shift with the 1CU, while the AT-45 paradoxically exhibited a small posterior shift. With the 1CU, the shift-induced accommodative effect was calculated to be less than +0.5 D in most cases, while +1 D was achieved in a single case only. Ranges and standard deviations were very large in relation to the mean values. Under physiological near-point stimulation, however, no shift was seen at all. Prevention of capsule fibrosis by extensive capsule polishing did not enhance the functional performance. Dual optic lenses are under clinical investigation and are reported to provide a significant amount of accommodation. However, possible long-term formation of interlenticular opacifications remains to be excluded. Regarding magnet-driven active-shift lens systems, initial clinical experience has been promising. Prevention of fibrotic capsular contraction is crucial, and it has been effectively counteracted with a special capsular tension ring, or lens fixation technique, together with capsule polishing. Lens refilling has been extensively studied in the laboratory and in primates. Though it offers great potential for fully restoring accommodation, a variety of problems must be solved, such as achieving emmetropia in the relaxed state, adequate response to ciliary muscle contraction, satisfying image quality over the entire range of accommodation and sustained functioning. The key problem, however, is again after-cataract prevention.

CONCLUSIONS: As opposed to psychophysical evaluation techniques, laser interferometry measures what shift lenses are designed to provide: axial shift on accommodative effort. While under pilocarpine some movement was recorded, no movement at all was found under near-point stimulation with any of the lenses currently marketed. In contrast, magnetic-driven active-shift lens systems carry the potential of sufficiently topping up apparent accommodation to provide for clinically useful accommodation while using conventional lens designs with proven after-cataract performance. Dual optic implants significantly increase the impact of axial optic shift. The main potential problem, however, is delayed formation of interlenticular regenerates. Lens refilling procedures offer the potential of fully restoring accommodation due to the great impact of increase in surface curvature on refractive lens power. However, various problems remain to be solved before clinical use can be envisaged, above all, again, after-cataract prevention. The concept of passive single-optic shift lenses has failed. Concomitant poor capsular bag performance makes these lenses an unacceptable trade-off. Magnet-assisted systems potentially combine clinically useful accommodation with satisfactory after-cataract performance. Dual optic lenses theoretically offer substantial accommodative potential but may allow for interlenticular after-cataract formation. Lens refilling procedures have the greatest potential for fully restoring natural accommodation, but will again require years of extensive laboratory and animal investigations before they may function in the human eye.

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Accurate determination of effective lens position and lens-capsule distance with 4 intraocular lenses.

J Cataract Refract Surg, 1998; 1094-8

PURPOSE: To measure effective lens position (ELP) of 4 intraocular lenses (IOLs) using high precision and high resolution dual-beam partial coherence interferometry (PCI) and to assess the tendency of these IOLs to produce a lens-capsule distance (LCD), a possible risk factor for posterior capsule opacification.

SETTING: Department of Ophthalmology, Vienna General Hospital; Institute of Medical Physics, University of Vienna, Austria.

METHODS: In a retrospective study, PCI was used to measure ELP and LCD in 139 pseudophakic eyes of 110 patients with 4 IOLs: acrylic 3-piece IOL (AcrySof MA60BM); silicone 3-piece IOL without a capsular tension ring (PhacoFlex SI30) and with a capsular tension ring (PhacoFlex SI30 and Morcher Type 14); silicone plate-haptic IOL (Staar AA4203VF); and a hydrogel plate-haptic IOL (logel 1103).

RESULTS: The ELP and LCD were determined with a precision of approximately 3 to 4 microns. An LCD was detected in 21% eyes with the AcrySof, 20% of eyes with the SI30 without a capsular tension ring, 10% of eyes with a capsular tension ring, 21% of eyes with the Staar, and 17% of eyes with the logel. The LCDs detected by PCI, but not by slitlamp examination, were significantly smaller than those detected by both.

CONCLUSION: The amount of LCD detected by PCI was approximately the same with all IOL types (approximately 20%) except the PhacoFlex SI30 with a capsular tension ring (10%).

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Acetazolamide-induced cerebral and ocular vasodilation in humans is independent of nitric oxide.

Am. J. Physiol., 1999; R1661-7

Acetazolamide, a carbonic anhydrase inhibitor, is used orally in the treatment of primary and secondary open-angle glaucoma and induces ocular and cerebral vasodilation. Several in vitro studies have shown that carbonic anhydrase pharmacology and the L-arginine-nitric oxide (NO) pathway are closely related. We investigated the role of NO in acetazolamide-induced vasodilation on cerebral and ocular vessels in 12 healthy subjects in the presence or absence of NG-monomethyl-L-arginine (L-NMMA), a NO synthase inhibitor, and in the presence or absence of L-arginine, the precursor of NO. Acetazolamide was administered after pretreatment with either L-NMMA or placebo and either L-arginine or placebo. Pulsatile choroidal blood flow was assessed with laser interferometric measurement of fundus pulsation. In addition, mean blood flow velocity (MFV) in the middle cerebral artery (MCA) and ophthalmic artery (OA) was measured with Doppler sonography. Acetazolamide increased ocular fundus pulsation amplitude (FPA; +27%, P < 0.001) and MFV in the MCA (+38%, P < 0.001) and in the OA (+19%, P = 0.003). Administration of L-NMMA alone reduced FPA (-21%, P < 0.001) and MFV in the MCA (-11%, P = 0. 030) but did not change MFV in the OA. All hemodynamic effects of L-NMMA were reversed by L-arginine. However, neither L-NMMA nor L-arginine altered acetazolamide-induced changes in cerebral or ocular hemodynamic parameters. The present data indicate that acetazolamide-induced hemodynamic changes are not mediated by NO. Which mediators other than NO are involved in the hemodynamic effects as induced by carbonic anhydrase inhibitors remains to be elucidated.

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Advantage of three dimensional animated teaching over traditional surgical videos for teaching ophthalmic surgery: a randomised study.

Br J Ophthalmol, 2005; 1495-9

BACKGROUND/AIM: Owing to the complex topographical aspects of ophthalmic surgery, teaching with conventional surgical videos has led to a poor understanding among medical students. A novel multimedia three dimensional (3D) computer animated program, called "Ophthalmic Operation Vienna" has been developed, where surgical videos are accompanied by 3D animated sequences of all surgical steps for five operations. The aim of the study was to assess the effect of 3D animations on the understanding of cataract and glaucoma surgery among medical students.

METHOD: Set in the Medical University of Vienna, Department of Ophthalmology, 172 students were randomised into two groups: a 3D group (n=90), that saw the 3D animations and video sequences, and a control group (n=82), that saw only the surgical videos. The narrated text was identical for both groups. After the presentation, students were questioned and tested using multiple choice questions.

RESULTS: Students in the 3D group found the interactive multimedia teaching methods to be a valuable supplement to the conventional surgical videos. The 3D group outperformed the control group not only in topographical understanding by 16% (p<0.0001), but also in theoretical understanding by 7% (p<0.003). Women in the 3D group gained most by 19% over the control group (p<0.0001).

CONCLUSIONS: The use of 3D animations lead to a better understanding of difficult surgical topics among medical students, especially for female users. Gender related benefits of using multimedia should be further explored.

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After-cataract in adults with primary posterior capsulorhexis: comparison of hydrogel and silicone intraocular lenses with round edges after 2 years.

J Cataract Refract Surg, 2003; 955-60

PURPOSE: To evaluate the potential of primary posterior continuous curvilinear capsulorhexis (PCCC) to prevent after-cataract 2 years after surgery and perform a bilateral comparison of 2 intraocular lens (IOL) materials, silicone and hydrogel.

SETTING: Department of Ophthalmology, University of Vienna, Medical School, Vienna, Austria.

METHODS: In this randomized patient- and examiner-masked study, 37 patients (74 eyes) with age-related cataract had bilateral small-incision cataract surgery with PCCC. Randomly, 1 eye received a hydrogel IOL and the contralateral eye, a silicone IOL. Both IOLs had open-loop haptics and a round-edged optic. Standardized digital retroillumination photographs were taken 1 day and 1, 6, 12, and 24 months after surgery to evaluate development of after-cataract on the anterior and posterior capsules by subjective grading. Opacification of the PCCC area was also objectively evaluated using new software.

RESULTS: Twenty-nine patients (58 eyes) completed the 2-year follow-up. Partial closure with ongrowth at the edge of the PCCC was found in 55% in the hydrogel group and 28% in the silicone group. Total closure of the PCCC was observed in 3 eyes, 2 in the hydrogel group and 1 in the silicone group.

CONCLUSION: Ongrowth onto the PCCC area was dependent on IOL material. Because of less ongrowth and more fibrotic after-cataract with silicone IOLs, the efficacy of the PCCC was higher in this group.

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Age dependence of choroidal blood flow.

J Am Geriatr Soc, 1998; 484-7

OBJECTIVE: To investigate the age dependence of choroidal blood flow.

DESIGN: A cross-sectional study.

SETTING: Department of Clinical Pharmacology, Vienna University.

PARTICIPANTS: A total of 130 healthy volunteers between the ages of 19 and 83 years.

MEASUREMENTS: Fundus pulsation amplitude (FPA) with a recently developed laser interferometric method, mean arterial pressure (MAP) with an automated oscillometric device, intraocular pressure (IOP) with an applanation tonometer, and ocular perfusion pressure (OPP) as calculated from MAP and IOP.

RESULTS: There was a significant correlation of FPA with age r = -0.242 (P = .005). MAP, IOP, and OPP showed a significant positive correlation with age. Multiple regression analysis showed that FPA is associated with age but not with MAP, IOP, or OPP.

CONCLUSION: Choroidal blood flow is reduced in older subjects, which argues in favor of an increase in ocular vascular resistance with age. This may be a risk factor in the development of common ocular diseases such as age-related macular degeneration or glaucoma.

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Age dependence of perimacular white blood cell flux during isometric exercise.

Curr. Eye Res., 2000; 757-62

PURPOSE: To investigate the age dependence of perimacular white blood cell flux (WBCF) during isometric exercise.

METHODS: Fourteen healthy young (age range: 21-29 years; 24 +/- 3 years, mean +/- SD, 12 male and 2 female) and 15 healthy middle-aged (age range: 45-57 years; 53 +/- 4 years, mean +/- SD; 5 male and 10 female) volunteers were studied. Subjects performed isometric handgrip for 10 minutes and squatting for 6 minutes. WBCF was assessed with the blue field entoptic technique, mean arterial pressure (MAP) was measured with an automated oscillometric device, intraocular pressure (IOP) was measured by Goldmann applanation tonometry and ocular perfusion pressure (OPP) was calculated as 2/3 MAP - IOP.

RESULTS: Baseline WBCF was significantly higher in young subjects than in middle-aged subjects (191 +/- 28 vs 142 +/- 23; p = 0.001). Isometric handgrip induced a significant increase in WBCF in the middle-aged subjects (23 +/- 24%; p = 0.005), but not in the young subjects. Squatting significantly increased WBCF in both groups (young: 42 +/- 23%; p = 0.004 and middle aged: 51 +/- 27%; p < 0.001). A significant deviation from baseline WBCF was observed when OPP increased by 42 +/- 4% (p = 0.003) and 35 +/- 4% (p < 0.001) for the young and middle-aged subjects, respectively. The OPP-WBCF relationship was not different between the two study groups.

CONCLUSION: Altered retinal autoregulation as observed in vascular ocular disease appears to be unrelated to the normal physiological aging process.

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Analysis of nonlinear systems to estimate intraocular lens position after cataract surgery.

J Cataract Refract Surg, 2004; 863-6

PURPOSE: To compare the performance of neural networks with that of linear regression to predict the postoperative effective lens position (ELP) from preoperative biometry measurements.

SETTING: Departments of Ophthalmology, Medical Cybernetics and Artificial Intelligence, and Medical Physics, Medical University of Vienna, Vienna, Austria.

METHODS: The neural-network-type multilayer perceptron (MLP) and a linear regression technique were used to predict ELP. Suitable MLP models and variable input combinations were selected by extended-feature subset selection. Apart from the usual preoperative biometric variables, anterior chamber depth and lens thickness were measured with partial coherence interferometry and white-to-white measurements were used as input variables.

RESULTS: Prediction of ELP could be improved from a correlation coefficient (Pearson) of 0.54 for linear regression to a coefficient of 0.68 for the MLP; however, this difference was not statistically significant.

CONCLUSION: The prediction of postoperative ACD with the MLP was not significantly better than the prediction using linear regression.

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Anterior capsulotomy created by radiofrequency endodiathermy and continuous curvilinear posterior capsulorhexis in a patient with intumescent cataract and primary capsular fibrosis.

J Cataract Refract Surg, 1998; 870-1

A 62-year-old woman with intumescent cataract and primary posterior capsular fibrosis was operated on using two different techniques to create continuous curvilinear capsule openings in the same eye. The biomicroscopic appearance of the edge after continuous tear and radiofrequency endodiathermy capsulotomy were compared.

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Assessment of a new averaging algorithm to increase the sensitivity of axial eye length measurement with optical biometry in eyes with dense cataract.

J Cataract Refract Surg, 2011; 45-9

PURPOSE: To assess the capability of new software to decrease the proportion of eyes that have insufficient signal-to-noise ratio (SNR) in optical biometry.

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

DESIGN: Evaluation of diagnostic test or technology.

METHODS: In a prospective study, consecutive cataract patients coming for biometry who were unsuccessfully measured with the former software (version 4) of the IOLMaster partial coherence interferometry (PCI) device were reevaluated with the new composite software (version 5). Subsequently, in a retrospective study, consecutive cataract patients were measured with software version 5. For unsuccessful scans, the type and intensity of cataract were assessed at the slitlamp.

RESULTS: Altogether, 2713 eyes (1956 patients) were included in the study. The prospective study comprised 458 eyes (244 patients), 10.6% of which could not be measured successfully with software version 4. With the composite software, 30% of cases were measured successfully, with a higher proportion (42%) in the posterior subcapsular cataract subgroup. In the retrospective study, of 2255 eyes (1712 patients), 4.7% were not measured successfully using the new algorithm because of white cataract (70 eyes), posterior subcapsular cataract (14 eyes), or dense nuclear cataract combined with posterior subcapsular cataract (13 eyes) or for other reasons (8 eyes).

CONCLUSION: The composite software (version 5) enhanced the SNR, allowing valid measurements in eyes in which optical biometry had previously failed, especially in cases of posterior subcapsular cataract.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned. Additional disclosure is found in the footnotes.

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Assessment of anterior capsule opacification: photographic technique and quantification.

J Cataract Refract Surg, 2002; 271-5

PURPOSE: To develop and evaluate a standardized slitlamp photographic technique to document and quantify anterior capsule opacification (ACO) in the pseudophakic eye.

SETTING: University of Vienna, Medical School, Department of Ophthalmology, Vienna, Austria.

METHODS: In this prospective study, slitlamp photographs were taken in 29 eyes of 19 patients with ACO of varying degrees and intraocular lenses of different materials. Digital slitlamp photographs were taken by 2 examiners using a standardized protocol. The intensity of anterior fibrosis was evaluated using subjective grading by 2 masked examiners and by image analysis.

RESULTS: A standardized protocol was developed for documentation of ACO. The intraexaminer (or short-term) reproducibility (r = 0.96, P < .01) and interexaminer reproducibility (r = 0.93, P < .01) were excellent. The results of image analysis used to objectively quantify ACO correlated with the subjective grading (r = 0.95, P < .01).

CONCLUSION: This standardized technique of slitlamp photography and image analysis provided reproducible documentation and can therefore serve as a basis for the quantification of ACO.

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Assessment of optic disk blood flow in patients with open-angle glaucoma.

Am. J. Ophthalmol., 2000; 589-96

PURPOSE: To characterize optic disk blood flow in patients with open-angle glaucoma compared with age-matched healthy control subjects.

METHODS: In this prospective cross-sectional study, 90 eyes of 90 patients with open-angle glaucoma and 61 eyes of 61 age-matched healthy control subjects were evaluated. Flow in the optic disk cup and the neuroretinal rim were assessed with scanning laser Doppler flowmetry. Fundus pulsation amplitude in the cup and the macula were assessed with laser interferometry. Visual field mean deviation was measured with the Humphrey 30 to 2 program.

RESULTS: Flow in the neuroretinal rim (-18%, P =.002), and in the cup (-46%, P <.001) and fundus pulsation amplitude in the cup (-33%, P <.001) and in the macula (-24%, P <.001) were significantly lower in patients with open-angle glaucoma compared with healthy control subjects. A significant association between blood flow measurements in the cup and fundus pulsation amplitudes in the cup was observed in both study cohorts. A significant association was also observed between the mean defect from visual field testing and ocular hemodynamic parameters.

CONCLUSIONS: Reduced optic disk perfusion in patients with open-angle glaucoma is evidenced from two independent methods in the present study. Moreover, our data indicate that reduced ocular blood flow in these patients is linked to visual field changes. It remains to be established whether compromised optic disk and choroidal blood flow contributes to optic disk damage in glaucomatous eyes or is a secondary functional phenomenon.

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Association between intensity of posterior capsule opacification and contrast sensitivity.

Am. J. Ophthalmol., 2005; 927-30

PURPOSE: To investigate the correlation between change in contrast sensitivity (CS) and difference in objective posterior capsule opacification (PCO) score before and after Nd:YAG laser capsulotomy.

DESIGN: Prospective interventional case series.

METHODS: CS (Functional Acuity Contrast Test, or FACT, chart), distance visual acuity (Early Treatment Diabetic Retinopathy Study [ETDRS] chart), and pupil size of 30 pseudophakic eyes with PCO of varying intensity were measured before and after capsulotomy. Digital retroillumination images were taken, and the area corresponding to the pupil size was evaluated with an automated PCO analysis program known as AQUA.

RESULTS: The correlation between change in PCO score and change in CS was highest (r = 0.85) for row B on the FACT chart and lowest (r = 0.09) for row E. The correlation with change in ETDRS visual acuity was 0.57.

CONCLUSIONS: Objective PCO assessment by an automated image analysis system correlates well with PCO-induced loss of CS and is therefore an appropriate method for clinical studies on the development and prevention of PCO.

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Association between intensity of posterior capsule opacification and visual acuity.

J Cataract Refract Surg, 2005; 543-7

PURPOSE: To investigate the correlation between the change in visual acuity and the difference in objective posterior capsule opacification (PCO) scores before and after neodymium:YAG (Nd:YAG) laser capsulotomy.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: Forty pseudophakic eyes of 35 patients with PCO of varying intensity were examined before and after Nd:YAG laser capsulotomy. Visual acuity was determined using the Early Treatment Diabetic Retinopathy Study (ETDRS) chart at 4 m and the Holladay reading chart at 40 cm. The pupil diameter under reading conditions was measured each time. Digital retroillumination images of the posterior capsule were taken, and the corresponding area inside the pupil was evaluated using the Automated Quantification of After-Cataract (AQUA) automated PCO analysis program. The change in visual acuity and difference between PCO scores before and after Nd:YAG laser capsulotomy were calculated for all eyes.

RESULTS: The mean AQUA score (scale 0 to 10) was 3.56 before and 0.13 after Nd:YAG laser capsulotomy. The mean ETDRS visual acuity score (logMAR scale) was 0.28 and -0.07, respectively. The correlation coefficient between the differences in PCO score and distance visual acuity was 0.61 and near visual acuity, 0.62.

CONCLUSIONS: The objective PCO score obtained by an automated image-analysis program correlates well with the PCO-induced decrease in visual acuity when the central area (inside the pupillary aperture) of the posterior lens capsule was evaluated. Objective PCO assessment by automated image-analysis systems is, therefore, a valuable and clinically relevant method for clinical studies of the development and prevention of PCO.

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Biometric investigation of changes in the anterior eye segment during accommodation.

Vision Res., 1997; 2789-800

Non-invasive biometry of the anterior structures of the human eye can be performed with unprecedented precision of 8-10 microns and a resolution of approximately 9 microns by partial coherence interferometry, which has the potential to assess the effect of cycloplegia on the ocular components of the anterior eye segment, to further improve the precision to 1-2 microns by the use of these agents and to quantify the amount of residual accommodations in different states of cycloplegia. In addition, the anterior chamber depth, the thickness of the crystalline lens, their changes during accommodation, as well as the movement of the anterior and posterior lens pole during accommodation can be quantified objectively and accurately to investigate the mechanism of accommodation.

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Biometry and intraocular lens power calculation.

Curr Opin Ophthalmol, 2005; 61-4

This article surveys the literature of 1 year, between July 2003 and August 2004, on the topic of biometry and intraocular lens power calculation for cataract surgery. There is an increasing demand for low postoperative refractive error with rising patient expectations, especially with patients who have already undergone refractive surgery, and with developing intraocular lens technologies such as multifocal, accommodating, or toric intraocular lenses. Optical biometry has become an invaluable tool for axial length measurement, especially for a setting with a less experienced biometrist. Introduction of ray tracing for power calculation and new methods of dealing with power calculation in eyes that have undergone previous refractive surgery seem promising. New intraocular lens designs that allow adjusting the axial optic position and therefore the effective refractive power of the intraocular lens have been evaluated in animal studies.

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Biometry of cataractous eyes using partial coherence interferometry: clinical feasibility study of a commercial prototype I.

J Cataract Refract Surg, 2002; 224-9

PURPOSE: To evaluate the clinical feasibility of the prototype version of a commercial partial coherence interferometry instrument (axial length measurement, ALM, Carl Zeiss Jena) for noninvasive, high-precision biometry in cataractous eyes.

SETTING: Department of Ophthalmology, Vienna General Hospital, and Institute of Medical Physics, University of Vienna, Austria.

METHODS: The preoperative axial length in 49 eyes of 37 cataract patients was measured with the commercial (ALM) and laboratory (PCI) prototypes of the partial coherence interferometry instrument, as well as with immersion ultrasound (IUS).

RESULTS: Axial length measurements with the ALM and PCI did not differ significantly (P = .23). Both prototypes assessed longer axial lengths than the IUS technique (P < .0001; median 203 microm; range -476 to +635 microm). The precision of the axial length measurement was 18 microm, 28 microm, and 54 microm with the PCI, ALM, and IUS, respectively.

CONCLUSIONS: Partial coherence tomography is a high-precision, high-resolution, noncontact biometric technique.The commercial PCI prototype is practical in clinical use, with improved comfort for patients, no need for anesthesia, and a reduced risk of infection. However, the difference between the PCI and IUS in axial length measurement must be considered when using the constants supplied by intraocular lens (IOL) manufacturers for IOL power calculations.

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Capsular bag performance of a hydrophobic acrylic 1-piece intraocular lens.

J Cataract Refract Surg, 2015; 90-7

PURPOSE: To compare parameters after 1-piece and 3-piece intraocular lens (IOL) implantation.

SETTING: Moorfields West End Clinic, London, United Kingdom, and Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective randomized controlled trial.

METHODS: Each eye of patients having bilateral surgery for age-related cataract was randomized to have implantation of a 1-piece IOL (Tecnis ZCB00) or a 3-piece IOL (Tecnis ZA9003). Changes in visual acuity, refraction, and anterior chamber depth (ACD) were evaluated during a 2-year follow-up. Intraocular lens tilt and decentration were evaluated using a Purkinje meter. Regeneratory posterior capsule opacification (PCO) was analyzed using retroillumination photographs in Automated Quantification of After-Cataract image-analysis software.

RESULTS: This study comprised 100 eyes of 50 patients. No statistically significant differences were found in IOL tilt or decentration between groups (P≥.06). Minimal but statistically significant changes were observed in the vertical tilt component 12 months postoperatively in the 3-piece IOL group (P<.01). The tilt and decentration components did not correlate with changes in sphere or the regeneratory PCO score (r = 0.38, P≥.06). The ACD decreased significantly between 1 day and 1 month postoperatively in both groups (P<.01), with no significant changes afterward (P≥.22). The anterior chamber was significantly deeper in the 1-piece group at all follow-up visits (P<.01).

CONCLUSIONS: Both the 1-piece IOL and the 3-piece IOL showed excellent positional stability in the capsular bag, resulting in good clinical outcomes. Regeneratory PCO levels were low and comparable between the IOLs.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

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Capsular bag stability and posterior capsule opacification of a plate-haptic design microincision cataract surgery intraocular lens: 3-year results of a randomised trial.

Br J Ophthalmol, 2013; 1565-8

PURPOSE: To compare capsular bag stability and posterior capsule opacification (PCO) of a plate-haptic intraocular lens (IOL) and a standard three-piece open-loop-haptic IOL of the same acrylic material.

METHODS: In this randomised bilateral patient-masked and examiner-masked study, each patient received a microincision cataract surgery IOL (MICS IOL; Acri.Smart 46S=CT SHERIS 209M) in one eye and a small incision cataract surgery IOL (SICS IOL; AcriLyc 53N = CT 53N, both Carl Zeiss Meditec AG, Germany) as a control in the contralateral eye. Follow-up examinations were performed 1 h, 1 week, 1 month, 1 year and 3 years postoperatively. Anterior chamber depth (ACD) was measured and retroillumination images were performed at all postoperative follow-ups. Furthermore, uncorrected and corrected distance visual acuity, autorefraction and subjective refraction were assessed.

RESULTS: In total, 50 eyes of 25 patients were included. The ACD difference between the MICS IOL and the SICS IOL was not significant at any time point (p>0.05). Distance-corrected visual acuity at the 3-year follow-up was similar and not significantly different between the groups (p=0.48). Mean AQUA score in the MICS IOL group and in the SICS IOL group at the 3-year follow-up was 2.3 (SD ±2.3) and 2.1 (SD ±2.2), respectively (p=0.79).

CONCLUSIONS: The investigated hydrophilic acrylic plate-haptic MICS IOL with a hydrophobic surface showed comparable results concerning capsular bag stability and PCO rates up to 3 years compared with a SICS IOL of the same material.

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The capsular tension ring: designs, applications, and techniques.

J Cataract Refract Surg, 2000; 898-912

Originally, the open poly(methyl methacrylate) (PMMA) capsular tension ring (CTR) was designed to compensate for zonular defects or to stretch the posterior capsule in highly myopic eyes not receiving an intraocular lens (IOL). We address the variety of subsequent designs, applications, and techniques that have evolved. With pre-existing or intraoperative zonular defects, a standard CTR may be inserted before or at any time during cataract removal to maintain or re-establish an extended capsular diaphragm. For profound zonular dialysis or weakness, a CTR was designed for scleral fixation. Capsular tension rings with integrated tinted sector shields have been developed to compensate for sector iris colobomas or aniridia. The CTR has also been used as a measuring gauge for in vivo quantification of capsule dimensions and postoperative capsular shrinkage. The CTR has improved control during primary posterior capsulorhexis and prevented oval distortion along the lens axis postoperatively. During combined cataract and vitreous surgery, a CTR prevents capsule damage and provides undisturbed peripheral visualization before IOL implantation. Capsular tension rings may also influence capsule opacification formation. A special band-shaped CTR with sharp edges was developed to inhibit lens epithelial cell migration and avoid capsulorhexis-optic contact.

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Central corneal thickness measurements with partial coherence interferometry, ultrasound, and the Orbscan system.

Ophthalmology, 2004; 875-9

OBJECTIVE: To compare the reliability of central corneal thickness measurements (CCT) obtained with partial coherence interferometry (PCI), ultrasound pachymetry, and the Orbscan system.

DESIGN: Cross-sectional study.

PARTICIPANTS: Twenty healthy subjects with CCT measurements in both eyes.

METHODS: The CCT measurements were obtained with PCI, ultrasound pachymetry, and the Orbscan system. In each eye, 2 investigators performed 5 repeated measurements with each pachymetric device. Intraclass correlation coefficients (kappa) were calculated and mean CCT measurements were compared.

MAIN OUTCOME MEASURES: The CCT measurements obtained with ultrasound pachymetry, the Orbscan system (Orbtek Inc., Salt Lake City, UT), and PCI.

RESULTS: Mean CCT values measured with ultrasound pachymetry were significantly thicker than those measured with PCI (21.5 microm; P<0.001) or the Orbscan system (19.8 microm; P<0.001). The correlation coefficients for the intraobserver variability were 0.999 for PCI measurements, 0.983 for ultrasound pachymetry measurements, and 0.988 for Orbscan system measurements. The correlation coefficients for the interobserver variability were 0.998 for PCI measurements, 0.980 for ultrasound pachymetry measurements, and 0.988 for Orbscan system measurements. There was a slightly better consistency between ultrasound pachymetry and PCI (kappa = 0.96) than between the Orbscan system and PCI (kappa = 0.92) and between ultrasound pachymetry and the Orbscan system (kappa = 0.89).

CONCLUSIONS: Partial coherence interferometry was the method with the least intraobserver or interobserver variability. Mean CCT as measured with ultrasound pachymetry was approximately 20 microm thicker than with the Orbscan system and PCI. However, corneal thickness measurements with ultrasound pachymetry and PCI were slightly more consistent than those of the Orbscan system and PCI. This slightly better consistency, however, may be important, especially in corneal refractive surgery.

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Cerebral and ocular hemodynamic effects of sumatriptan in the nitroglycerin headache model.

Clin. Pharmacol. Ther., 1996; 199-205

BACKGROUND AND PURPOSE: Sumatriptan is a selective 5-hydroxytryptamine1d (5-HT1d)-receptor agonist, highly effective in the short-term treatment of migraine headaches. However, the mechanism underlying the action of sumatriptan is not yet completely understood. To further characterize the vascular effects of sumatriptan, we studied the effects on cerebral and ocular circulation in the well-established nitroglycerin headache model.

METHODS: In a double-blind, placebo-controlled, randomized, two-way crossover study in 10 healthy male subjects, we administered either placebo plus nitroglycerin or sumatriptan plus nitroglycerin. Blood flow velocity in the middle cerebral artery and the ophthalmic artery, as well as ocular fundus pulsations and systemic hemodynamic parameters, were measured after sumatriptan and placebo and during the following infusion of nitroglycerin.

RESULTS: After infusion of nitroglycerin, blood flow velocity in the middle cerebral decreased by -13.3% versus baseline after placebo pretreatment, but by only -2.2% after sumatriptan (treatment effect, +10.8%; p < 0.05). In contrast, sumatriptan had no effect in the ophthalmic artery. Ocular fundus pulsations, which estimate local pulsatile ocular blood flow, were slightly reduced after sumatriptan. Moreover, sumatriptan partially prevented the increase in fundus pulsations during nitroglycerin infusion (treatment effect, -5.4%; p < 0.05).

CONCLUSIONS: Sumatriptan prevents the effect of nitroglycerin-induced vasodilation in the middle cerebral artery but not in the ophthalmic artery, which strongly supports the concept that sumatriptan directly vasoconstricts distended basal cerebral arteries. Measurement of ocular fundus pulsations indicates that sumatriptan also has a small vasoconstrictor action on resistance vessels.

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Change in IOL position and capsular bag size with an angulated intraocular lens early after cataract surgery.

J Cataract Refract Surg, 2005; 348-53

PURPOSE: To investigate the axial movement in the first postoperative week and the influence of capsular bag size with an angulated, 3-piece, open-loop, acrylic intraocular lens (IOL).

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: Twenty-nine eyes of 29 patients with age-related cataract were included in this study. In study 1, an open-loop, 3-piece IOL (AR40e, AMO) was implanted in a standardized fashion in 15 eyes of 15 patients. In study 2, before IOL implantation, a capsular tension ring (CTR) was inserted (14 eyes of 14 patients). Anterior chamber depth (ACD) was assessed with partial coherence interferometry 2 hours; 1, 3, and 5 days; 1 week; and 1 month postoperatively. The capsular bag diameter (CBD) was assessed using gonioscopic measurement of the eyelets of the CTR 1 day, 1 week, and 1 month postoperatively.

RESULTS: In the first postoperative week, there was a significant mean forward movement of -196 microm +/- 117 (SD) (P < .005) in study 1 and -139 +/- 97 microm in study 2 (P < .005). These movements correspond to refractive changes of -0.31 diopter (D) and -0.20 D, respectively. The movement was linear in the first 5 days after surgery. Different patterns of early postoperative movement were seen, illustrating interindividual variability. A significant correlation of 0.67 (P < .05) was found between the change in ACD and CBD.

CONCLUSIONS: A linear forward movement of the IOL during the first postoperative week was followed by a relatively stable IOL position. Loss of haptic memory seemed to be the most likely cause. Myopic eyes with large capsular bags showed less IOL shift in the early postoperative period than hyperopic eyes with smaller capsular bags.

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Changes in intraocular lens position after neodymium: YAG capsulotomy.

J Cataract Refract Surg, 1999; 659-62

PURPOSE: To quantify changes in intraocular lens (IOL) position caused by neodymium: YAG (Nd:YAG) capsulotomy with 3 IOL styles.

SETTING: Department of Ophthalmology, University of Vienna, Austria.

METHODS: In a prospective study, anterior chamber depth (ACD) was measured by dualbeam partial coherence interferometry (PCI) in 32 pseudophakic eyes of 32 patients with posterior capsule opacification before and immediately after planned capsulotomy under mydriasis. Patients were divided into 3 groups with the following IOL styles: 1-piece poly(methyl methacrylate) (PMMA), 3-piece foldable, and plate haptic.

RESULTS: The capsulotomy induced a backward IOL movement in all 32 eyes (mean 25 microns; range 9 to 55 microns). It was more pronounced in eyes with plate-haptic IOLs than in those with the other styles. Precision of ACD measurement by PCI was 4 microns. Changes in ACD correlated significantly with capsulotomy size but not with preoperative lens-capsule distance.

CONCLUSION: Capsulotomy caused a backward movement of the IOL, which was more pronounced with plate-haptic IOLs than with 1-piece PMMA and 3-piece foldable IOLs. Since the magnitude of IOL movement in this study population was small, a hyperopic shift in refraction after capsulotomy will usually be small and not clinically relevant.

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Choroidal blood flow and arterial blood pressure.

Eye (Lond), 2003; 84-8

PURPOSE: Untreated hypertension is associated with ocular complications and is a risk factor for the development and progression of vascular ocular pathologies. We set out to investigate the association between systemic blood pressure and choroidal blood flow.

METHODS: All subjects were male non-smokers, who did not receive any medication and had normal or slightly elevated blood pressure (systolic blood pressure < or = 160 mmHg; diastolic blood pressure < or = 100 mmHg). The association between systemic blood pressure and fundus pulsation amplitude, a measure of pulsatile choroidal blood flow, was investigated in 318 volunteers. In addition, the association between systemic blood pressure and blood flow velocities in the posterior ciliary arteries supplying the choroid was investigated in these subjects.

RESULTS: Ocular fundus pulsation amplitude (r = 0.252; P < 0.001) and mean flow velocity in the posterior ciliary arteries (r = 0.346, P < 0.001) were significantly associated with mean arterial pressure. The correlation of ocular haemodynamic variables with systolic and diastolic blood pressure was in the same range.

CONCLUSIONS: Our data indicate a small, but significant increase in choroidal blood flow with increasing blood pressure.

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Clinical effects of primary posterior continuous curvilinear capsulorhexis in eyes with single-piece hydrophilic acrylic intraocular lenses with and without haptic angulation.

J Cataract Refract Surg, 2007; 258-64

PURPOSE: To evaluate the clinical effects of a primary posterior continuous curvilinear capsulorhexis (PCCC) on the intraocular performance of hydrophilic acrylic single-piece intraocular lenses (IOLs) with and without haptic angulation.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: A prospective study comprised 52 patients with bilateral age-related cataract who had standard cataract surgery including a PCCC. One eye of each patient was randomized to receive a hydrophilic acrylic IOL with haptic angulation (ACR6D SE, Laboratoires Cornéal) and the contralateral eye, a hydrophilic acrylic IOL without haptic angulation (C-flex 570C, Rayner). The following parameters were assessed: regeneratory posterior opacification (RPO) in the central, intermediate, and peripheral areas (scale 0 to 10); anterior capsule opacification (ACO); best corrected visual acuity (BCVA); and contrast sensitivity (CSF).

RESULTS: Thirty-one patients completed the 1(1/2)-year follow-up. In both IOL groups, RPO within the PCCC was slight in the central area, with a mean score of 0.33 +/- 0.84 (SD) in the angulated IOL group and 0.16 +/- 0.57 in the nonangulated IOL group (P = .29). The mean RPO score in the peripheral area was 2.07 +/- 1.37 and 2.35 +/- 1.45, respectively (P = .12). The difference between the central and peripheral areas was 1.74 in the angulated IOL group (P<.00001) and 2.19 in the nonangulated IOL group (P<.00001). Haptic deformation occurred in 9 eyes (29%) with an angulated IOL and no eye with a nonangulated IOL. There was significantly more ACO in the nonangulated IOL group (P = .012). There were no significant differences in BCVA or CSF between the 2 groups.

CONCLUSIONS: Creating a PCCC led to significantly lower RPO intensity within the PCCC area than in the peripheral area in eyes with hydrophilic acrylic IOLs with and without haptic angulation. Haptic angulation had no apparent significant influence on the intensity of RPO or on BCVA and CSF. Haptic deformation may occur in hydrophilic IOLs with angulated haptics.

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Comparability of anterior chamber depth measurements with partial coherence interferometry and optical low-coherence reflectometry in pseudophakic eyes.

J Cataract Refract Surg, 2015; 1678-84

PURPOSE: To assess whether anterior chamber depth (ACD) measurements in pseudophakic eyes obtained with partial coherence interferometry (PCI) and optical low-coherence reflectometry (OLCR) devices can be used interchangeably.

SETTING: Vienna Institute for Research in Ocular Surgery, A Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective case series.

METHODS: The ACD measurements in 1 eye of each pseudophakic patient were performed with the PCI-based ACMaster device and the OLCR-based Lenstar LS900 device at least 1 day postoperatively.

RESULTS: The study comprised 65 eyes of 65 patients with a mean age of 71.7 years ± 9.0 (SD) (range 39 to 91 years). In 15 eyes, no valid ACD readings could be obtained with the OLCR device. No obvious reason for these measurement failures was identified; however, tear-film alterations shortly after surgery were suspected. No significant difference in the mean ACD in the remaining 50 eyes was found between PCI measurements (5019 ± 660 μm; range 4008 to 6181 μm) and OLCR measurements (5015 ± 663 μm; range 4017 to 6163 μm) (P = .06). Three (6%) of 50 measurements were not within the 95% limits of agreement in the Bland-Altman analysis.

CONCLUSIONS: Pseudophakic ACD measurements with the PCI and OLCR devices can be used interchangeably. The OLCR device proved to be more user-friendly and faster; however, in a substantial number of eyes, no usable values were obtainable.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

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Comparative analysis of optical biometers.

J Cataract Refract Surg, 2016; 685-93

PURPOSE: To evaluate the level of agreement, repeatability, and correlation of 2 optical biometers, the IOLMaster (based on partial coherence interferometry [PCI]) and Aladdin (based on optical low-coherence interferometry [OLCI]) in terms of axial length (AL), mean keratometry (K), anterior chamber depth (ACD), and corneal diameter.

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

DESIGN: Prospective comparative case series.

METHODS: Each participant had biometry with both biometers. The level of agreement between the biometers was calculated using the Bland-Altman method. Double-angle polar plots were used to display the astigmatism vectors. Internal consistency was computed with the Cronbach α coefficient of reliability, whereas the dispersion of probability distribution was assessed with the coefficient of variation (CoV). The intraoperator repeatability was analyzed using the intraclass correlation coefficient (ICC); the AL was evaluated in all eyes and the mean K and the ACD in a subset of eyes.

RESULTS: The study comprised 215 eyes; the ICC for the mean K and ACD was calculated in a subset of 54 eyes. There was a statistically significant difference between the 2 biometers in all measurements (P < .05). The level of agreement was high with both methods. The ICC and internal consistency were excellent with both biometers; the CoVs were low.

CONCLUSIONS: The OLCI biometer provided good agreement and repeatability compared with the PCI biometer, the current gold standard in ocular biometry. Further comparative studies are necessary to clearly define the role of the OLCI biometer in predicting postoperative refractive outcomes.

FINANCIAL DISCLOSURES: Dr. Findl is a scientific advisor to Carl Zeiss Meditec AG. None of the other authors has a financial or proprietary interest in any material or method mentioned.

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Comparative study of corneal topographic changes after 3.0 mm beveled and hinged clear corneal incisions.

J Cataract Refract Surg, 1998; 1498-504

PURPOSE: To compare the corneal topographic changes after cataract surgery using 2 types of clear corneal incisions (CCIs).

SETTING: Department of Ophthalmology, University of Vienna, Austria.

METHODS: This prospective, unmasked, nonrandomized study comprised 64 eyes scheduled for cataract surgery; 29 eyes received a temporal sutureless 3.0 mm corneal beveled CCI and 35 eyes, a temporal sutureless 3.0 mm hinged CCI. Preoperatively and 1 week, 1 and 3 months, and 1 year postoperatively, corneal topography was recorded by computer-assisted videokeratoscopy (TMS-1, Computed Anatomy, Inc.). Data were evaluated by batch-by-batch analyses of the paired differences between these records. The significance of topographic changes was calculated by paired Wilcoxon tests, and group comparisons were made using Wilcoxon tests.

RESULTS: In both groups, there was statistically significant horizontal flattening and lower corneal steepening (P < .01). The horizontal flattening decreased between 1 week and 1 year, from -0.6 to -0.3 diopter (D) in the beveled-incision group and -0.7 to -0.4 D in the hinged-incision group. Vertical steepening was significant in the lower corneal region and decreased between 1 week and 1 year, from 0.3 to 0.2 D. Group comparisons revealed significant differences in an oblique lower temporal semimeridian, with 0.1 to 0.3 D more steepening after the hinged incision than after the beveled incision (P < .05).

CONCLUSION: There were only minimal differences between beveled and hinged CCIs in surgically induced corneal shape changes.

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Comparing capsular bag performance of a hydrophilic and a hydrophobic intraocular lens: A randomised two-centre study.

Eur J Ophthalmol, 2018; 1120672117752133

PURPOSE: To evaluate the capsular bag performance and posterior capsule opacification development of two intraocular lenses differing in material and design.

METHODS: This study included patients who were scheduled for cataract surgery and compared a hydrophilic intraocular lens (Super flex intraocular lens; Rayner Surgical, Worthing, UK) with a hydrophobic intraocular lens (AcrySof SA60AT; Alcon, Fort Worth, TX, USA). Follow-ups were performed 1 month and 2 years after cataract surgery, including a slit lamp examination and retroillumination images.

RESULTS: In total, 80 eyes of 80 patients were recruited. At the 1-month follow-up, 6 of 39 cases had a gap between the posterior lens capsule and intraocular lens (1 case in the hydrophilic intraocular lens group and 5 cases in the hydrophobic intraocular lens group; p = 0.348). Objective and subjective posterior capsule opacification scoring showed no statistically significant difference between both groups (p = 0.123).

CONCLUSION: Both intraocular lens showed a good capsular bag performance and a relatively low posterior capsule opacification development within the first 2 years after surgery.

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A comparison between laser interferometric measurement of fundus pulsation and pneumotonometric measurement of pulsatile ocular blood flow. 1. Baseline considerations.

Eye (Lond), 2000; 39-45

PURPOSE: Several methods have been proposed for the investigation of the human choroidal circulation. The aim of the present study was to compare laser interferometric measurements of cardiac synchronous fundus pulsations with pneumotonometric measurements of intraocular pressure pulse and pulsatile ocular blood flow in humans.

METHODS: The association between fundus pulsation amplitude as assessed with laser interferometry and pulse amplitude (PA) and pulsatile ocular blood flow (POBF) as assessed with pneumotonometry was investigated in 28 healthy subjects. Additionally, we investigated the distribution of fundus pulsation amplitude (FPA) in a region of -15 degrees to +15 degrees around the macula (n = 18) and the influence of accommodation paralysis with cyclopentolate on FPA (n = 10).

RESULTS: There was a high association between FPA and PA (r = 0.86, p < 0.001) and FPA and POBF (r = 0.70, p < 0.001). Fundus pulsations in the macula were significantly smaller than in the optic disc, but significantly larger than those in peripheral regions of the retina. Administration of cyclopentolate did not influence FPA.

CONCLUSIONS: On the basis of the strong correlation between laser interferometric measurements of FPA and pneumotonometric measurements of PA and POBF, we conclude that the FPA is a valid index of pulsatile choroidal perfusion in humans.

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A comparison between laser interferometric measurement of fundus pulsation and pneumotonometric measurement of pulsatile ocular blood flow. 2. Effects of changes in pCO2 and pO2 and of isoproterenol.

Eye (Lond), 2000; 46-52

PURPOSE: We have shown in the companion paper that, under baseline conditions, there is a high degree of association between laser interferometrically measured fundus pulsation amplitude (FPA) and pneumotonometrically measured pulse amplitude (PA) and pulsatile ocular blood flow (POBF). The present study investigated the effect of high pCO2, of high pO2 and of isoproterenol on POBF as assessed with laser interferometry and pneumotonometry.

METHODS: Pneumotonometry and laser interferometry were performed in young healthy subjects during breathing of 100% O2 (n = 10; hyperoxia) and of 5% CO2 + 95% air (n = 8; hypercapnia). In addition these parameters were studied during stepwise increasing doses of isoproterenol, a beta-receptor agonist (n = 8).

RESULTS: Inhalation of 5% CO2 + 95% air increased FPA (24 +/- 12%, p < 0.001), PA (26 +/- 13%, p < 0.001) and POBF (15 +/- 8%, p = 0.002). Inhalation of 100% O2 decreased FPA (-5 +/- 7%, p = 0.027), but did not change PA or POBF. The effect of 100% O2 inhalation on FPA in the optic disc was more pronounced (-11% to -20%) than in the macula. Isoproterenol caused a dose-dependent increase in FPA, PA and POBF (p < 0.001). The association between the induced changes in FPA and PA or POBF was highly significant.

CONCLUSIONS: The present study shows that FPA can be taken as a valid relative measure of pulsatile choroidal blood flow. Our results in the optic disc indicate that FPA at the neuroretinal rim and at the cup is influenced by retinal and choroidal circulation.

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Comparison of 4 methods for quantifying posterior capsule opacification.

J Cataract Refract Surg, 2003; 106-11

PURPOSE: To compare the results of posterior capsule opacification (PCO) quantification and the repeatability of a fully automated analysis system (Automated Quantification of After-Cataract [AQUA]) with that of 2 other quantification methods and subjective grading of PCO. A test set of digital retroillumination images of 100 eyes with PCO of varying degrees was used.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: One hundred digital retroillumination images of eyes (100 patients) with PCO were selected to attain an even distribution from mild to severe cases. The images were evaluated by 4 methods: subjective grading by 4 experienced and 4 inexperienced examiners, the subjective Evaluation of Posterior Capsular Opacification (EPCO) system, posterior capsule opacification (POCO) software, and the AQUA system. Ten images were presented twice to assess the reproducibility of the analysis systems.

RESULTS: Subjective grading correlated best with the subjective EPCO system and the objective AQUA system (r = 0.94 and r = 0.93, respectively). The POCO system showed very early saturation and therefore a much weaker correlation (r = 0.73). The POCO scores reached the maximum of 100% in several minimal to mild PCO cases. The reproducibility of the AQUA software was perfect and that of the other analysis systems, comparably satisfactory.

CONCLUSION: The objective AQUA score correlated well with subjective methods including the EPCO system. The POCO system, which assesses PCO area, did not adequately describe PCO intensity and includes a subjective step in the analysis process. The AQUA system could become an important tool for randomized masked trials of PCO inhibition.

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Comparison of 4 specular microscopes in healthy eyes and eyes with cornea guttata or corneal grafts.

Cornea, 2015; 381-6

PURPOSE: The aim of this study was to compare 4 noncontact specular microscopes for the assessment of the corneal endothelium in a heterogeneous sample of eyes.

METHODS: This prospective study included 22 healthy eyes, 16 eyes with cornea guttata and 31 eyes that had undergone penetrating keratoplasty or Descemet stripping automated endothelial keratoplasty. Corneal endothelial cell parameters of all eyes were assessed with the CellChek XL (Konan Medical, Hyogo, Japan), Perseus (Bon Optic, Lübeck, Germany), EM-3000 (Tomey, Nagoya, Japan), and CEM-530 (Nidek Co, Ltd, Gamagori, Japan) in a randomized order. Bland-Altman plots of interdevice agreement were produced. The time taken for data entry, scanning, and automated image analysis was recorded, and instrument repeatability was analyzed.

RESULTS: The mean age was 61 ± 19 years (range, 24-88). The measurement success rate was 100% in healthy corneas, ranged between 64.5% and 93.5% in eyes with corneal grafts, and between 0% and 18.8% in eyes with cornea guttata. Comparative analysis of endothelial cell parameters revealed significant differences in endothelial cell density readings in the total study population and in subgroups (P < 0.01).

CONCLUSIONS: The CEM-530 and Perseus were extremely fast, showed highly repeatable measurements, and are recommendable for screening purposes. The CellChek XL device was slower, but extensive postprocessing options and an exportable database make this instrument suitable for compromised corneas and for research purposes. The EM-3000 device ranged between the fast devices and the CellChek XL and comes with reliable automated cell-counting software. However, careful interpretation of results from automated image analysis software is mandatory.

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Comparison of anterior chamber depth measurement methods in phakic and pseudophakic eyes.

J Cataract Refract Surg, 2003; 89-94

PURPOSE: To compare anterior chamber depth (ACD) measurements in phakic and pseudophakic eyes using a slit-beam photographic technique (IOLMaster, Carl Zeiss Meditec AG) with those obtained with the laboratory prototype version of partial coherence interferometry (PCI) and with conventional applanation ultrasound in phakic eyes.

SETTING: Department of Ophthalmology, Vienna General Hospital, Vienna University, Vienna, Austria.

METHODS: Thirty-three ACDs of 28 patients with age-related cataract were measured preoperatively with a slit-beam photographic technique (IOLMaster) and the prototype version of PCI. In 24 eyes, the ACD was also assessed with applanation ultrasound. In addition, 34 ACDs of 18 pseudophakic patients in a different study population were examined postoperatively with the IOLMaster and PCI.

RESULTS: The median ACD in the phakic eyes was 3.06 mm (range 1.93 to 3.90 mm) with the IOLMaster, 3.09 mm with PCI (range 1.49 to 4.06 mm), and 2.87 mm (range 2.18 to 3.33 mm) with applanation ultrasound. The precision was 0.005 mm for PCI and 0.015 mm for IOLMaster measurement. The median difference between the IOLMaster and PCI ACD biometry was 0.01 mm +/- 0.14 (SD) (range -0.44 to 0.17 mm) (P =.71). In pseudophakic eyes, the 2 methods showed a median difference of -0.22 mm (range -0.45 to 1.99 mm) (P >.1) and did not correlate (r = 0.21; P >.2).

CONCLUSIONS: In phakic eyes, the difference between IOLMaster and PCI measurements was small and not statistically significant. In pseudophakic eyes, the difference was larger and the methods did not correlate.

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Comparison of corneal wetting properties of viscous eye lubricant and balanced salt solution to maintain optical clarity during cataract surgery.

J Cataract Refract Surg, 2011; 1806-8

PURPOSE: To compare the corneal wetting properties of balanced salt solution (BSS) and a viscous eye lubricant during cataract surgery.

SETTING: Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective randomized controlled study.

METHODS: This randomized controlled subject- and examiner-masked study comprised patients scheduled for cataract surgery. The patients were randomly assigned to receive either BSS or hydroxypropyl methylcellulose (HPMC) 2% gel (Cornea_Protect). Fluorescein staining, optical clarity during surgery, application frequency, subjective grading of discomfort, and subjective dryness of the eye were assessed.

RESULTS: One hundred one eyes of 97 patients (mean age 73.6 years; range 53 to 87 years) were included in the study. Mean grade of fluorescein staining was 9.46 ± 3.64 (SD) and 9.76 ± 3.27 (SD) in the BSS group and the HPMC 2% group, respectively (P=.67). Median grade of optical clarity during surgery was 2.0 in the BSS group and 1.0 in the HPMC 2% group, a statistically significant difference (P=.03). Median application frequency of BSS was 10 times higher than median application frequency of 1 time for HPMC 2%, a statistically significant difference (P<.001).

CONCLUSIONS: Hydroxypropyl methylcellulose 2% provided significantly better optical clarity than BSS during cataract surgery. Because frequent irrigation is not needed and HPMC 2% provides a better view for the surgeon, the use of HPMC 2% results in increased comfort for the patient, especially under topical anaesthesia, and in a simpler and possibly safer surgical procedure.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned. Additional disclosure is found in the footnotes.

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Comparison of intraocular lens decentration and tilt measurements using 2 Purkinje meter systems.

J Cataract Refract Surg, 2017; 648-655

PURPOSE: To evaluate the difference in intraocular lens tilt and decentration measurements with 2 Purkinje meters.

SETTING: Vienna Institute for Research in Ocular Surgery, Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective evaluation of diagnostic test.

METHODS: This single-center study included pseudophakic patients in 2 substudies in which 3 consecutive measurements were performed with 2 Purkinje meters (Spanish and German). In substudy 1, an inexperienced examiner performed all measurements after a short learning period. In substudy 2, all measurements were taken by experienced examiners under direct supervision of the inventors of the devices.

RESULTS: Substudy 1 included 53 pseudophakic eyes in which all 53 scans were successful with the Spanish device; however, only 35 measurements (66%) were successful with the German Purkinje meter. The mean tilt measured with the Spanish Purkinje meter was 4.35 degrees ± 2.50 (SD) and 9.20 ± 6.96 degrees with the German Purkinje meter. The mean decentration was 0.44 ± 0.19 mm and 0.74 ± 0.91 mm, (P = .44), respectively. In substudy 2 (29 pseudophakic eyes), the number of successful scans was 29 (100%) and 18 (62%) for the Spanish meter and German Purkinje meter, respectively. The mean horizontal and vertical tilt difference vector between the 2 systems was 4.89 ± 3.24 degrees and 7.57 ± 3.82 degrees, respectively.

CONCLUSIONS: Concerning clinical feasibility, the Spanish Purkinje meter had a greater percentage of successful scans than the German device. In addition, this device measured significantly higher tilt values than the Spanish Purkinje meter.

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Comparison of methods to quantify posterior capsule opacification using forward and backward light scattering.

J Cataract Refract Surg, 2014; 728-35

PURPOSE: To compare forward and backward light scattering measurements to quantify posterior capsule opacification (PCO).

SETTING: Vienna Institute for Research in Ocular Surgery, Vienna, Austria.

DESIGN: Prospective single-center study.

METHODS: This observational study comprised consecutive patients scheduled for neodymium:YAG (Nd:YAG) capsulotomy for regeneratory PCO. The corrected distance visual acuity (CDVA) using Early Treatment of Diabetic Retinopathy Study charts and the contrast sensitivity under mesopic and photopic conditions using Pelli-Robson charts were assessed before an Nd:YAG capsulotomy was performed. Retroillumination images, rotating Scheimpflug scans (Pentacam HR), and straylight meter (C-Quant) and point-spread function (PSF) meter (Optical Quality Analysis System) measurements were performed before and after Nd:YAG capsulotomy.

RESULTS: The study enrolled 50 eyes of 50 patients. The mean uncorrected distance visual acuity and CDVA were 0.76 logMAR ± 0.18 (SD) and 0.68 ± 0.2 logMAR, respectively. The mean log contrast sensitivity (logCS) was 1.2 ± 0.15 logCS under photopic conditions and 1.05 ± 0.15 logCS under mesopic conditions. There was a moderate correlation between the Scheimpflug score and the Automated Quantification of After-Cataract score (r(2) = 0.37, P=.03). Furthermore, a moderate and close to significant correlation between the PSF meter and the straylight meter was observed (r(2) = 0.32; P=.07).

CONCLUSION: Each of the 4 devices assesses different aspects of a patient's quality of vision. Further developments should focus on methods that measure forward scatter of light in a large visual angle and are not too patient or examiner dependent.

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Comparison of partial coherence interferometers: Acmaster versus laboratory prototype.

J Refract Surg, 2006; 811-6

PURPOSE: To evaluate anterior segment biometry using the ACMaster (Carl Zeiss Meditec AG, Jena, Germany) in regard to precision of measurement and clinical performance compared to the original laboratory prototype of the partial coherence interferometry technique.

METHODS: Ten phakic (20 eyes) and 27 pseudophakic (44 eyes) patients were included in this study. Anterior segment biometry of phakic and pseudophakic study eyes was performed using the ACMaster and the laboratory prototype of the partial coherence interferometry technique. The ACMaster is a commercially available device based on the partial coherence interferometry technique, which provides high precision anterior segment measurements in a quick and user-friendly fashion. Examination included measurement of central corneal thickness, anterior chamber depth, and lens thickness, the latter only in the phakic eyes.

RESULTS: The consistency of anterior segment measurements performed with both units was excellent in phakic as well as in pseudophakic eyes. In pseudophakic eyes, the measurement of anterior chamber thickness and lens thickness with the ACMaster produced several (typical) measurement artifacts in some cases, which partially aggravated the identification of the A-scan peak representing the anterior intraocular lens surface.

CONCLUSIONS: The ACMaster is a user-friendly device that enables axial anterior segment biometry using the partial coherence interferometry technique with a reproducibility similar to that of the original laboratory prototype.

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Comparison of pilocarpine-induced and stimulus-driven accommodation in phakic eyes.

Exp. Eye Res., 2005; 795-800

With the recent introduction of potentially accommodative intraocular lenses (IOL), there is a need for methods to evaluate their accommodative potential. In most studies assessing IOL movement, pilocarpine is used to stimulate contraction of the ciliary muscle. The aim of this study is to determine if pilocarpine-induced ciliary muscle contraction is comparable to physiological stimulus-driven accommodation in young and presbyopic subjects. Ten emmetropic young subjects (23-25 years) and 11 emmetropic presbyopic subjects (51-62 years) were included in this study. Anterior chamber depth (ACD) and lens thickness (LT) were assessed with partial coherence interferometry (PCI). A moveable stimulus was coupled to the PCI equipment for measurement of biometric lens changes. ACD was measured with the stimulus at infinity and then at the subjects individual nearpoint, and after application of two drops of 2% pilocarpine. In young subjects, there was no significant difference in lens change between nearpoint and pilocarpine stimulation. Presbyopic subjects showed no relevant lens change when accommodating at the nearpoint, however, under pharmacologically induced ciliary muscle contraction with pilocarpine, there was a significant forward shift of the anterior and posterior lens pole, leading to a translational forward lens shift of about 150 microm. This study demonstrates that pilocarpine acts "physiologically" in young phakic subjects, but is a "superstimulus" in presbyopic phakic subjects. Therefore, IOL movement may be overestimated when using pilocarpine to stimulate accommodation.

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Comparison of posterior capsule opacification between a 1-piece and a 3-piece microincision intraocular lens.

Br J Ophthalmol, 2013; 18-22

OBJECTIVE: To compare the intensity of posterior capsular opacification (PCO) between a 1-piece and a 3-piece microincision cataract surgery intraocular lens (MICS IOL) in a prospective randomised study.

METHODS: 80 eyes of 40 patients with age-related cataract were enrolled in this study. Each patient received a 1-piece MICS IOL (AF-1 NY-60, Hoya, Tokyo, Japan) in one eye and a 3-piece MICS IOL (AF-1 iMICS Y-60H, Tokyo, Hoya) in the other eye. At the 1-year follow-up, the patients were examined at the slit lamp, visual acuity was determined and standardised high-resolution digital retroillumination images were taken for objective quantification of regeneratory PCO using an automated image analysis software (AQUA).

RESULTS: The mean regeneratory PCO score (1-piece IOL: 0.2, 3-piece IOL 0.3, p=0.7) and the neodymium:yttrium-aluminium-garnet laser capsulotomy rate (two cases in 3-piece IOL group; p=0.5) were comparable low for both IOLs. Capsular folds occurred significantly more often in the 3-piece IOL group (p=0.02).

CONCLUSIONS: Modification of the MICS IOL from a 3-piece to a 1-piece haptic design caused in short term no significant change in PCO amount. Compared with the 3-piece IOL, the 1-piece IOL led to significantly less capsular folds 1 year after surgery.

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Comparison of posterior capsule opacification between the 1-piece and 3-piece Acrysof intraocular lenses: two-year results of a randomized trial.

Ophthalmology, 2004; 1840-6

PURPOSE: To compare intensity of posterior capsule opacification (PCO) between the 1-piece and 3-piece haptic designs of an open-loop hydrophobic acrylic intraocular lens (IOL).

DESIGN: A randomized, patient- and examiner-masked clinical trial with intraindividual comparison.

PARTICIPANTS: Fifty-two patients with bilateral age-related cataract (104 eyes).

METHODS: Each patient had cataract surgery in both eyes and received a 1-piece Acrysof IOL in one eye and a 3-piece Acrysof IOL in the fellow eye. Follow-up examinations were at 1 week, 1 month, 6 months, 1 year, and 2 years. Patients were examined at the slit lamp, visual acuity (VA) was determined, and standardized high-resolution digital retroillumination images of the posterior capsule were taken. The intensity of PCO was assessed subjectively at the slit lamp and objectively using automated image analysis software.

MAIN OUTCOME MEASURE: Posterior capsule opacification score (scale, 0-10).

RESULTS: There was no significant difference between IOL styles in best-corrected VA, rhexis/IOL overlap, capsular folds, and amount of anterior capsule opacification during the follow-up period. One year postoperatively, the amount of regeneratory PCO was higher for the 1-piece Acrysof eyes (image analysis software score: 1.3) than for the 3-piece Acrysof eyes (score: 0.9; P = 0.002). However, 2 years postoperatively, there was no significant difference between the 2 IOL styles (1-piece: 1.5; 3-piece: 1.3; P = 0.3). Neodymium:yttrium-aluminum-garnet capsulotomy was not performed in the study.

CONCLUSION: One year postoperatively, the 1-piece Acrysof showed slightly more regeneratory PCO than the 3-piece Acrysof. However, 2 years postoperatively, the barrier effect of the 1-piece design was comparable to that of the 3-piece haptic design, with low PCO intensity.

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Comparison of three methods of measuring corneal thickness and anterior chamber depth.

Am. J. Ophthalmol., 2006; 7-12

PURPOSE: To compare three different methods of measuring corneal thickness (CT) and anterior chamber depth (ACD).

DESIGN: Prospective clinical trial (Medical University of Vienna, Austria).

METHODS: Central CT (CCT), CT at four peripheral points, and central ACD were measured in 88 eyes of 44 healthy subjects with the Pentacam (rotating Scheimpflug camera; Oculus, Wetzlar, Germany), Orbscan I (scanning-slit topography system; Orbtek Inc, Salt Lake City, Utah, USA), and AC-Master (partial coherence interferometry; Zeiss Meditec, Jena, Germany), and the results were compared.

RESULTS: The upper (lower) limits of agreement for CCT measurements were 7.9 (-22.2) microm between AC-Master and Pentacam, 17.6 (-32.5) microm between AC-Master and Orbscan, and 25.2 (-25.9) microm between Pentacam and Orbscan. Correlation was high between all three methods (r = 0.94 to 0.97). The upper and lower limits of agreement for ACD were 0.174 (-0.251) mm between AC-Master and Pentacam, 0.406 (-0.004) mm between AC-Master and Orbscan, and 0.384 (0.095) mm between Pentacam and Orbscan. Correlation was high between the three methods (r = 0.96 between Orbscan and Pentacam; others 0.92). Correlation was lower for the CT measurements at the four peripheral points.

CONCLUSIONS: The CCT and ACD values obtained by Pentacam, Orbscan, and AC-Master measurements correlated well and showed few outliers. The two new systems (Pentacam, AC-Master) provide a reliable, easy-to-use, noncontact method of measuring CCT and ACD. Larger differences occurred only when measuring peripheral CT values, especially between AC-Master and the other two methods.

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Comparison of ultrasound pachymetry and partial coherence interferometry in the measurement of central corneal thickness.

J Cataract Refract Surg, 2002; 2142-5

PURPOSE: To compare central corneal thickness (CCT) measurements obtained with 3 ultrasound pachymeters and with partial coherence interferometry (PCI) and evaluate the effect of repeated contact by a pachymetry probe on corneal thickness.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: Central corneal thickness was measured in 20 eyes of 20 healthy volunteers with 3 different ultrasound pachymeters (DGH 500, DGH Technology Inc.; SP 2000, Tomey Inc.; Paxis, Biovision Inc.) and with PCI. In each eye, 5 measurements with PCI were followed by 5 measurements with each ultrasound pachymetry device and another 5 measurements with PCI.

RESULTS: The mean CCT measured with the DGH 500, SP 2000, and Paxis was 541.0 microm, 539.2 microm, and 545.1 microm, respectively. Although the differences among the 3 ultrasound pachymetry devices were within 6.0 microm, they were statistically significant (P<.05). The PCI measurements were significantly smaller (P <.05) than the ultrasound measurements: 518.8 microm before and 517.5 microm after repeated contact with the ultrasound pachymetry probe (P <.05). The mean precision (standard deviation) was 0.77 microm for PCI and between 2.40 microm and 3.58 microm for ultrasound pachymetry measurements. The correlation coefficients for the intraobserver variability were 0.999 for PCI and between 0.987 and 0.995 for ultrasound pachymetry measurements.

CONCLUSIONS: Partial coherence interferometry was the more precise method of measuring CCT and had better intraobserver variability. Repeated contact by a pachymetry probe reduced corneal thickness by 1.3 microm. However, the reason for the smaller measurements with PCI than with ultrasound pachymetry remains unclear.

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Computer-based tutorial to enhance the quality and efficiency of the informed-consent process for cataract surgery.

J Cataract Refract Surg, 2012; 655-9

PURPOSE: To assess whether informing patients with an interactive computer-based tool in addition to the face-to-face discussion with their physician is more effective than the conventional informed-consent procedure.

SETTING: Hanusch Hospital, Vienna, Austria.

DESIGN: Randomized controlled triple-masked clinical trial.

METHODS: Patients with bilateral cataract scheduled for cataract surgery at the same center were randomly allocated to a study group or a control group. Patients in the study group were given an interactive computer-based tool (CatInfo) containing a detailed audiovisual presentation about cataract and its treatment. Patients in the control group watched a short sham computer presentation without cataract-related information. Then, all patients had a face-to-face informed-consent discussion with a physician masked to group allocation. Afterward, patients in both groups received the same validated questionnaire with cataract-related questions.

RESULTS: The study group comprised 60 patients and the control group, 30 patients. The mean age was 73 years (range 51 to 90 years) and 75 years (range 48 to 94 years), respectively. Patients in the study group answered statistically significantly more questions correctly than patients in the control group (15 versus 12 of 19). There was an age effect in the study group, with the computerized tool having a greater impact on elderly patients.

CONCLUSIONS: Patients in the study group were significantly better informed than patients in the control group. These findings show that the interactive computer-based tool is a useful tutorial to achieve a better informed-consent process for cataract surgery.

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Conservative treatment of goiter with destrumin.

Ther Ggw, 1955; 181-2

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Consistent IOL calculation.

Ophthalmologe, 2001; 300-4

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Contact zone of piggyback acrylic intraocular lenses.

J Cataract Refract Surg, 1999; 860-2

In a hyperopic cataract patient, surgery was performed with implantation of 2 foldable, acrylic, posterior chamber intraocular lenses (IOLs) in the bag. The IOLs showed a central contact zone during surgery. This contact zone remained after surgery and was documented 2 months postoperatively. The contact zone may induce multifocality similar to that seen with multifocal IOLs.

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Corneal endothelial cell protection with a dispersive viscoelastic material and an irrigating solution during phacoemulsification: low-cost versus expensive combination.

J Cataract Refract Surg, 2003; 733-40

PURPOSE: To evaluate the protective effect on corneal endothelial cells of a low-cost and an expensive combination of a dispersive viscoelastic material and an irrigating solution during phacoemulsification.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This prospective randomized examiner- and patient-masked study comprised 90 eyes of 45 consecutive patients with age-related cataract in both eyes. For each patient, the first eye was randomly assigned to receive hydroxypropyl methylcellulose 2% (Ocucoat) and Ringer's solution (low-cost combination) or sodium chondroitin sulfate 4%-sodium hyaluronate 3% (Viscoat) and an enriched balanced salt solution (BSS Plus) (expensive combination) during phacoemulsification. The contralateral eye received the other treatment. Endothelial cell function was evaluated by measuring corneal thickness (CT) using partial coherence interferometry, morphology assessment, and endothelial cell counts.

RESULTS: The acute postoperative increase in CT was +9.8 microm in the low-cost group and +10.9 microm in the expensive group; the difference between groups was not significant. After 1 month, the CT still differed significantly from baseline in the low-cost group. Three months after surgery, the CT had returned to baseline values in both groups. There was no significant between-group difference in endothelial cell counts or morphology.

CONCLUSIONS: During phacoemulsification in a nonselected patient population, there was no difference in acute postoperative corneal edema and endothelial cell morphology after 3 months between a Viscoat and BSS Plus combination and an Ocucoat and Ringer's solution combination. Eyes receiving the expensive combination had marginally faster recovery of corneal swelling by 3 months. However, the cost of Viscoat and 500 mL BSS Plus is 5 times that of Ocucoat and Ringer's solution.

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Corneal shape changes after temporal and superolateral 3.0 mm clear corneal incisions.

J Cataract Refract Surg, 1999; 1121-6

PURPOSE: To compare the corneal topographic changes after temporal and superolateral 3.0 mm clear corneal incisions (CCIs) and implantation of foldable silicone intraocular lenses (IOLs).

SETTING: Department of Ophthalmology, University of Vienna, Austria, and a private clinic, Winterthur, Switzerland.

METHODS: This prospective study comprised 54 eyes of 54 patients scheduled for cataract surgery. After a 0.3 mm deep precut, a temporal 3.0 mm CCI was made in 26 eyes and a superolateral (at 10:30) 3.0 mm CCI in 28 eyes. Corneal topography was recorded preoperatively and 1 week and 1 and 3 months postoperatively using the TMS-1 computer-assisted videokeratoscope (Computed Anatomy, Inc.). Surgically induced corneal shape changes were evaluated by batch-by-batch analyses of the paired differences between the records. The significance of topographic changes was calculated by the paired Wilcoxon test; group comparisons were made using the Wilcoxon group comparison test.

RESULTS: Both groups had incision-related corneal flattening at 1 week and 1 and 3 months postoperatively. The extent of this flattening at 1 week and 1 and 3 months postoperatively was up to 1.0, 0.9, and 0.7 diopter (D), respectively, in the temporal group and up to 1.2 D at each observation time in the superolateral group. There was statistically significantly more incision-related corneal flattening in the superolateral incision group than in the temporal incision group; the difference was up to 0.3 D after 1 month and 0.5 D after 3 months.

CONCLUSION: The superolateral incision induced statistically significantly more incision-related corneal flattening than the temporal incision.

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Correction of moderate corneal astigmatism during cataract surgery: toric intraocular lens versus peripheral corneal relaxing incisions.

J Cataract Refract Surg, 2014; 354-61

PURPOSE: To compare the astigmatism-reducing effect of a toric intraocular lens (IOL) and peripheral corneal relaxing incisions (PCRIs).

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

DESIGN: Prospective masked bilateral randomized study.

METHODS: Cataract patients with a preoperative corneal astigmatism of 1.0 to 2.5 diopters (D) were included. All patients received a toric IOL in 1 eye and a nontoric IOL plus a PCRI in the other eye. Postoperative follow-up was at 1 hour, 1 month, and 6 months. The uncorrected distance visual acuity, corrected distance visual acuity, autorefraction (Topcon RM-8800), and subjective refraction were recorded. The IOL axis was assessed using retroillumination photographs.

RESULTS: The study enrolled 60 eyes of 30 patients. The mean astigmatism vector reduction was 1.74 D ± 0.64 (SD) in the toric IOL group and 1.27 ± 0.76 D in the PCRI group; the difference was statistically significant (P=.042). The mean absolute rotation of the toric IOL was 2.5 ± 1.8 degrees (maximum 6.3 degrees) in the first 6 postoperative months. Astigmatism increased in the PCRI group between the 1-month and 6-month follow-up (mean 0.38 ± 0.27 D; maximum 1.00 D) (P<.001).

CONCLUSION: Toric IOLs and PCRIs both reduced astigmatism; however, toric IOLs reduced astigmatism to a higher extent and they were more predictable.

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Correlation between the early morphological appearance of filtering blebs and outcome of trabeculectomy with mitomycin C.

J. Glaucoma, 2003; 430-5

PURPOSE: To correlate the morphologic appearance of filtering blebs in the early postoperative period with the outcome of trabeculectomy with mitomycin C (MMC) during the first postoperative year.

PATIENTS AND METHODS: In a prospective study, the morphologic appearance of filtering blebs after primary trabeculectomy with adjunctive MMC (0.1 mg/ml for 5 minutes intra-operatively) was classified; 49 eyes of 49 patients were examined preoperatively, 1 and 3 days, 1 and 2 weeks, 1, 3, 6, and 12 months postoperatively. Status of filtering bleb, intraocular pressure (IOP), and number of medications were recorded.

RESULTS: One year after surgery all patients had IOP < or = 21; 6 patients received antiglaucoma medication. One eye required needling of the filtering bleb because of encapsulation. During the first postoperative year, eyes with conjunctival subepithelial micro cysts, observed in the first and the second postoperative week, had significantly lower mean IOP, than eyes without (11.1 mm Hg vs. 13.9 mm Hg; p:0.0043, ANOVA). Eyes with corkscrew vessels, observed in the first and the second postoperative week, had significantly higher mean IOP, than eyes without during the first postoperative year (13.4 mm Hg vs. 11.7 mm Hg; p:0.0141, ANOVA).

CONCLUSION: Classification of filtering blebs after trabeculectomy with MMC may help to disclose patients with an increased failure risk.

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The course of myopia in children with mild retinopathy of prematurity.

Vision Res., 1995; 1329-35

The courses of spherical equivalent in patients (n = 62) who had mild, non-cicatricial retinopathy of prematurity (ROP), and in those without a history of ROP (n = 25) were modeled as a linear function of age; an exponential model was also considered. A few (n = 5) without ROP have abnormal courses characterized by hyperopia in early infancy; none have poor acuity. Although the majority of patients with ROP have courses indistinguishable from those of term born controls, 27 (43.5%) have abnormal courses, most of which are toward myopia. Optotype acuities were significantly poorer among the ROP patients with abnormal than normal refractive courses. Thus abnormal refractive development and acuity deficits are associated in eyes that have had mild ROP.

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Daily changes in the morphology of Elschnig pearls.

Am. J. Ophthalmol., 2006; 517-523

PURPOSE: To observe and document the daily changes in the morphology of Elschnig pearls.

DESIGN: A prospective cohort study.

METHODS: Twenty-nine pseudophakic eyes with pronounced, regeneratory posterior capsule opacification (PCO) were included in this prospective study. Retroillumination images were taken at days 0, 1, 2, and 14. A square grid was laid over the images. Increase, decrease, appearance, and disappearance of pearls between the follow-up images were quantified.

RESULTS: A total of 1371 areas (mean: 53/eye) of 26 eyes were analyzed between days 0 and 1 and 1 and 2, and 896 areas (50/eye) of 18 eyes between days 0 and 14. Between days 0 and 1, days 1 and 2, and days 0 and 14, we observed "no change" in pearl size in 72%, 77%, and 32%, a "minor increase" in 16%, 14%, and 10%, a "major increase" in 4%, 3%, and 42%, a "minor decrease" in 14%, 11%, and 11%, and a "major decrease" in 4%, 3%, and 37%, respectively. Appearance of newly formed pearls was found in 1%, 1%, and 9% and disappearance of pearls in 1%, 1%, and 5%, respectively.

CONCLUSIONS: Significant changes in the morphology of Elschnig pearls were observed within time intervals of only 24 hours. Appearance and disappearance of pearls, as well as progression and regression of pearls within these short intervals illustrate the dynamic behavior of regeneratory PCO. These findings may contribute to a better understanding of PCO and have implications on pharmaceutical interventions for PCO.

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Dark-adapted thresholds in children with histories of mild retinopathy of prematurity.

Invest. Ophthalmol. Vis. Sci., 1997; 1175-83

PURPOSE: To test the hypothesis that rod-mediated visual thresholds at 10 degrees eccentricity are elevated in children with histories of mild retinopathy of prematurity (ROP).

METHODS: Dark-adapted thresholds for detection of 50 msec, 2 degrees diameter spots at a 10 degrees eccentric site, and at a peripheral reference site, 30 degrees eccentric, were measured in 20 children with a history of mild ROP and known courses of refractive development. Ten myopic control subjects also were tested. The thresholds of the ROP and control subjects were compared.

RESULTS: Six of the subjects with ROP had elevated thresholds at the 10 degrees site. High myopia had been present since age 18 months or younger in each of the six. The thresholds of all other subjects with ROP, whose courses of refractive development had been toward emmetropia, and the control subjects with myopia were normal. In subjects with ROP, the association of early, persistent high myopia and an elevated threshold at 10 degrees was significant (chi 2 = 20; P < 0.01). Among the subjects with ROP, refractive error and axial length were correlated.

CONCLUSIONS: ROP or factors causing ROP appear to alter rod-mediated retinal function. The association of abnormal rod-mediated sensitivity and refractive development suggests that rod-mediated retinal function is involved in the regulation of eye growth in children with a history of mild ROP.

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Depth of focus after implantation of spherical or aspheric intraocular lenses in hyperopic and emmetropic patients.

J Cataract Refract Surg, 2017; 1413-1419

PURPOSE: To evaluate whether hyperopic patients with short axial length and high dioptric intraocular lens (IOL) power can achieve a higher depth of focus after implantation of a monofocal spherical or aspheric IOL than emmetropic patients.

SETTING: Department of Ophthalmology, Medical University Graz, Graz, Austria.

DESIGN: Prospective case series.

METHODS: Patients presenting for cataract surgery were divided by calculated IOL power into a hyperopic (≥22.0 diopters [D]) or emmetropic (18.0 to 21.5 D) groups and received an aspheric (Tecnis ZA9003) or a spherical IOL (Sensar AR40e). Postoperative measurements included corrected (CDVA) and uncorrected (UDVA) distance visual acuities, distance-corrected intermediate (DCIVA) and near (DCNVA) visual acuities, root-mean-square values of corneal and total eye higher-order aberrations and spherical aberrations, and photopic and mesopic contrast sensitivity.

RESULTS: Sixty-two eyes of 62 patients were enrolled in this study, 34 eyes (15 hyperopic, 19 emmetropic) in the aspheric IOL group and 28 eyes (14 hyperopic, 14 emmetropic) in the spherical IOL group. The UDVA, CDVA, and contrast sensitivity did not differ significantly between the 2 IOL groups, whereas the DCIVA and DCNVA were significantly better in the spherical IOL group (P = .004 and P = .001, respectively). No significant differences were found in DCIVA and DCNVA between hyperopic patients and emmetropic patients with aspheric or spherical IOLs.

CONCLUSIONS: Implantation of a monofocal spherical IOL resulted in an increased depth of focus without significant degradation of distance visual acuity or contrast sensitivity. There were no differences in the depth of focus between hyperopic eyes and emmetropic eyes.

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Determining postoperative anterior chamber depth.

J Cataract Refract Surg, 2003; 2122-6

PURPOSE: To compare measured and calculated postoperative anterior chamber depths (ACDs).

SETTING: Department of Ophthalmology and Institute of Medical Physics, University of Vienna, Vienna, Austria, and Department of Ophthalmology, University of Mainz, Mainz, Germany.

METHODS: The postoperative ACD was measured in 189 pseudophakic eyes using a laboratory prototype of partial coherence interferometry (PCI). In 6 intraocular lens (IOL) groups, the mean ACD was calculated by ray tracing based on the best-known A-constants of the SRK formulas. In addition, for each IOL type, each measured ACD was compared with a value calculated using the individual spherical equivalent of the postoperative refraction.

RESULTS: The measured and the calculated ACD values were close and did not show systematic differences. The ACD values obtained in the study, however, differed significantly from the values published by the IOL manufacturers. A comparison of the PCI-assessed ACDs and the calculated values using the postoperative refraction showed more scattered results for the refraction-based data, which was probably the result of higher measurement errors with the autorefractometer than with PCI.

CONCLUSIONS: High-precision interferometry measurements and ray-tracing calculations confirmed each other. The resulting mean ACD values should be used instead of the manufacturers' values. The refractive outcome of cataract surgery can be improved by combining preoperative high-precision PCI biometry and numerical ray tracing for IOL power calculations.

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The development of the rod photoresponse from dark-adapted rats.

Invest. Ophthalmol. Vis. Sci., 1995; 1038-45

PURPOSE: To study electroretinographic a- and b-wave responses of rats at the ages during which rod outer segment length (ROS) and rhodopsin content increase.

METHODS: Electroretinographic responses to brief, full-field stimuli were recorded from dark-adapted young (ages 12 to 30 days) and adult rats. The amplitude of the a-wave and the amplitude and implicit time of the b-wave were examined as a function of stimulus intensity. Sensitivity (S), saturated amplitude (RmP3), and delay (td) of the rod cell responses were calculated from the a-waves.

RESULTS: The developmental increase in saturated a-wave amplitude parallels, but lags behind, growth of outer segment length, whereas the saturated b-wave amplitude increases with about the same course as rhodopsin content of the retina. The sensitivity, S, depends on rhodopsin content, and the developmental decrease in the flash energy required to produce a half-maximum b-wave amplitude is inversely proportional to the developmental increase in rhodopsin content. No significant age-dependent variation in td can be detected.

CONCLUSION: During development, ROS length and rhodopsin content of the retina are significant determinants of a- and b-wave response parameters.

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Diagnostic precision of a microscope-integrated intraoperative OCT device in patients with epiretinal membranes.

Eur J Ophthalmol, 2018; 329-332

PURPOSE: Preoperative and postoperative optical coherence tomography (OCT) of macular pathologies can be regarded as the gold standard diagnostic technique, providing detailed information on the microstructures of the macula for planning the surgical procedure and comparing improvements after surgery in the follow-up period. Intraoperative use of OCT is a novel application to support surgeons during macular surgery. The aim of this study was to examine the diagnostic precision of a microscope-integrated intraoperative spectral-domain OCT (i-OCT) device and compare imaging results to a stand-alone spectral-domain OCT (SD-OCT) device.

METHODS: This prospective study included 41 eyes of 41 patients scheduled for pars plana vitrectomy with membrane peeling due to an idiopathic epiretinal membrane (ERM). Intraoperative imaging with the i-OCT device was performed at the beginning of the surgery and compared to preoperative SD-OCT images.

RESULTS: Preoperative and intraoperative SD-OCT evaluations showed high intraobserver and interobserver reproducibility for the presence of ERM, lamellar macular hole, and vitreomacular traction. For intraretinal cystoid changes, intraobserver and interobserver reproducibility for both OCTs was rather poor, mainly due to microcystic changes.

CONCLUSIONS: Intraoperative spectral-domain OCT offers high reproducibility regarding the visibility of ERM, lamellar macular holes, and vitreomacular traction. Microcystic changes cause discrepancies in interpretation, often simply diagnosed as retinal thickening.

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Does perfluoro-n-octane use in 23G vitrectomy for retinal detachment surgery affect the integrity of the ellipsoid zone?

Eur J Ophthalmol, 2016; 639-642

PURPOSE: To examine the integrity of the ellipsoid zone after perfluoro-n-octane use for reattachment of the central retina in macula-off retinal detachment cases.

METHODS: Intraoperative video documentation with microscope-integrated intraoperative spectral-domain optical coherence tomography (OCT) of 10 consecutive patients with macula-off retinal detachment, scheduled for primary vitrectomy for retinal detachment repair, was retrospectively examined for defects in the integrity of the ellipsoid zone due to perfluoro-n-octane use.

RESULTS: Successful intraoperative visualization was possible in all cases, retinal detachment was reattached in all cases, but residual islands of subretinal fluid persisted directly after perfluoro-n-octane use in 80% of cases. These were resorbed in all cases in the postoperative OCTs. Disturbances in the integrity of the ellipsoid zone or intraoperative macular hole formation did not present in any of our cases.

CONCLUSIONS: Perfluoro-n-octane use seems to be a safe procedure regarding integrity of the ellipsoid zone in cases scheduled for primary vitrectomy for retinal detachment repair.

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A double masked placebo controlled study on the effect of nifedipine on optic nerve blood flow and visual field function in patients with open angle glaucoma.

Br J Clin Pharmacol, 2001; 210-2

AIMS: To investigate whether nifedipine affects ocular perfusion or visual fields in open angle glaucoma patients.

METHODS: In a parallel group study nifedipine or placebo was administered for 3 months (n = 30). Ocular fundus pulsation amplitude (FPA), cup blood flow (Flowcup) and visual field mean deviation (MD) were measured.

RESULTS: Five patients receiving nifedipine discontinued due to adverse events. Nifedipine did not affect FPA [difference: 0.3 microm (95% CI -0.3,0.9); P = 0.70], Flowcup: [difference: -9 rel.units (95% CI -133,114); P = 0.99], or MD [difference: 0.2dB (95% CI -2.2,2.7); P = 0.51] vs placebo.

CONCLUSIONS: Systemic nifedipine is not well tolerated in glaucoma patients and exerts no effect on visual fields or ocular perfusion.

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Dual beam optical coherence tomography: signal identification for ophthalmologic diagnosis.

J Biomed Opt, 1998; 55-65

The dual beam version of optical coherence topography can be used for noninvasive, high-resolution imaging of the human eye fundus, enabling in vivo visualization of retinal morphology as well as accurate quantification of the thickness profiles of its layers. Interferometric fundus signals-optical A-scans-and retinal tomograms of patients with glaucoma, diabetic retinopathy, and age-related macular degeneration are compared with those of healthy, normal subjects to elucidate the origin of the signal peaks detected and to investigate and interpret the retinal microstructures contained in the cross-sectional images. © 1998 Society of Photo-Optical Instrumentation Engineers.

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Early objective assessment of intraocular inflammation after phacoemulsification cataract surgery.

J Cataract Refract Surg, 2003; 2143-7

PURPOSE: To evaluate the time course of blood-aqueous barrier (BAB) disturbance in the early period after small-incision cataract surgery.

SETTING: Department of Ophthalmology, Vienna University, Vienna, Austria.

METHODS: In a prospective study, 15 eyes of 15 patients with age-related cataract had small-incision cataract surgery by phacoemulsification with intraocular lens implantation. Care was taken to minimize trauma to the uvea during surgery. Postoperative inflammation was assessed by measuring aqueous flare and cell count with a laser flare-cell meter. Postoperative measurements were performed hourly for the first 6 hours, every 2 hours until 12 hours, every 4 hours until 40 hours, and every 8 hours until 56 hours.

RESULTS: The time course of aqueous flare and cell count differed significantly among patients. The peak inflammatory response in most cases was 1 hour after surgery, with the response decreasing thereafter. The pattern of the time course was classified into subgroups defined by the presence and size of an initial spike immediately after surgery and the intensity of the subsequent inflammatory reaction. A slight increase in flare and cells was seen in the morning hours of the first postoperative day.

CONCLUSIONS: Acute BAB disturbance within the first 48 hours after small-incision cataract surgery showed high interpatient variability. However, many differences were not detectable 1 day after surgery.

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Effect of a capsular tension ring on axial intraocular lens position.

J Cataract Refract Surg, 2015; 122-5

PURPOSE: To assess the effect of a capsular tension ring (CTR) on the postoperative anterior chamber depth (ACD).

SETTING: Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective observer- and patient-masked randomized trial.

METHODS: Bilateral small-incision cataract surgery with implantation of a hydrophobic acrylic single-piece intraocular lens (IOL) (Tecnis ZCB00) was performed using a standard technique. Each patient received a CTR in 1 eye (CTR group) and no CTR in the fellow eye (control group). The ACD was measured preoperatively with biometry (IOLMaster 500) and at 1 hour and 12 weeks postoperatively using partial coherence interferometry (ACMaster). The subjective refraction was assessed at 12 weeks.

RESULTS: Sixty eyes (30 patients) were included. Preoperatively, the mean axial length was 23.36 mm ± 1.55 (SD) (range 21.01 to 29.46 mm) in the CTR group and 23.37 ± 1.70 mm (range 21.14 to 28.84 mm) in the control group and the mean ACD was 3.06 ± 0.45 mm (range 2.25 to 4.16 mm) and 3.03 ± 0.47 mm (range 2.18 to 4.10 mm), respectively. The differences were not statistically significant (P=.148 and P=.074, respectively). The mean postoperative ACD was 4.83 ± 0.46 mm (range 3.84 to 5.76 mm) in the CTR group and 4.81 ± 0.43 mm (range 3.67 to 5.65 mm) in the control group. The difference between the groups was not statistically significant (P=.329).

CONCLUSION: Implantation of a CTR had no significant influence on the postoperative axial IOL position.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

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Effect of a fixed dorzolamide-timolol combination on intraocular pressure after small-incision cataract surgery with Viscoat.

J Cataract Refract Surg, 2003; 1748-52

PURPOSE: To evaluate the effect of a fixed dorzolamide-timolol combination (Cosopt) on intraocular pressure (IOP) after small-incision cataract surgery with sodium chondroitin sulfate 4%-sodium hyaluronate 3% (Viscoat).

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This prospective randomized study comprised 76 eyes of 38 patients scheduled for small-incision cataract surgery in both eyes. Patients were randomized to receive 1 drop of the fixed dorzolamide-timolol combination in 1 eye or no treatment (control) immediately after cataract surgery. The fellow eye received the other assigned treatment. Cataract surgery was performed with Viscoat in an identical fashion in both eyes. The IOP was measured preoperatively and 6 hours, 20 to 24 hours, and 1 week postoperatively.

RESULTS: Six hours after surgery, the mean increase in IOP was significantly lower in the dorzolamide-timolol group than in the control group (4.3 mm Hg +/- 5.6 [SD] versus 8.4 +/- 6.1 mm Hg; P =.003). Two eyes in the dorzolamide-timolol group and 9 in the control group had IOP spikes of 30 mm Hg or higher (P =.022). Twenty to 24 hours after surgery, the mean IOP change was -2.6 +/- 3.3 mm Hg in the dorzolamide-timolol group and 1.5 +/- 3.2 mm Hg in the control group (P<.001).

CONCLUSIONS: The fixed dorzolamide-timolol combination was effective in reducing IOP 6 hours and 20 to 24 hours after cataract surgery. However, it did not prevent Viscoat-induced IOP spikes of 30 mm Hg or higher.

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Effect of a new cohesive ophthalmic viscosurgical device on corneal protection and intraocular pressure in small-incision cataract surgery.

J Cataract Refract Surg, 2008; 1362-6

PURPOSE: To compare the corneal protective and intraocular pressure (IOP) effects of a new cohesive ophthalmic viscosurgical (OVD), Neocrom Cohesive (sodium hyaluronate 1.4%), with those of Healon (sodium hyaluronate 1.0%) in cataract surgery.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: This randomized patient-masked examiner-masked study with fellow-eye comparison comprised 29 cataract surgery patients. Surgery was performed with Neocrom Cohesive in 1 eye and Healon in the other eye. Central corneal thickness (CCT) was measured preoperatively and 1 day and 3 months postoperatively; endothelial cell density (ECD), preoperatively and 3 months postoperatively; and IOP, preoperatively and 6 hours and 1 day postoperatively.

RESULTS: The mean CCT change from preoperatively to postoperatively in the Neocrom Cohesive, respectively, group and Healon group was +16.0 microm +/- 25.7 (SD) (P<.01) and +7.0 +/- 17.1 microm (P<.05), respectively, at 1 day and -5.7 +/- 10.8 microm (P<.01) and -4.7 microm +/- 9.5 microm) (P<.01), respectively, at 3 months. The mean ECD change at 3 months was 8 +/- 155 cells/mm(2) in the Neocrom Cohesive group (P = .8) and -46 +/- 139 cells/mm(2) in the Healon group (P = .08). The mean IOP increase was +2.2 +/- 3.5 mm Hg (P<.01) and +1.4 +/- 4.2 mm Hg (P = .14), respectively, 6 hours postoperatively and +0.9 +/- 4.3 mm Hg (P = .37) and 0.0 +/- 3.5 mm Hg (P = .77), respectively, at 1 day.

CONCLUSION: There was no significant difference between Neocrom Cohesive and Healon in the changes in CCT, ECD, and IOP after cataract surgery.

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Effect of a silicone intraocular lens with a sharp posterior optic edge on posterior capsule opacification.

J Cataract Refract Surg, 2004; 1661-7

PURPOSE: To compare the inhibiting effect on posterior capsule opacification (PCO) of a silicone intraocular lens (IOL) with a sharp posterior optic edge (ClariFlex OptiEdge, Advanced Medical Optics) and a silicone IOL with a round optic edge (PhacoFlex SI-40, Advanced Medical Optics).

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This prospective randomized patient- and examiner-masked study comprised 104 eyes of 52 patients with bilateral age-related cataract. All patients had cataract surgery in both eyes and received a sharp-edged IOL in 1 eye and a round-edged IOL in the other eye. Postoperative examinations were at 1 week, 1 and 6 months, and 1 year. Digital slitlamp and retroillumination images were taken of each eye. The amount of PCO was assessed subjectively at the slitlamp and objectively using Automated Quantification of After-Cataract (AQUA) automated-image analysis software.

RESULTS: The sharp-edged IOL group had significantly less regeneratory and fibrotic PCO 1 month, 6 months, and 1 year after surgery. The mean AQUA PCO score (scale 0 to 10) was 0.71 in the sharp-edged IOL group and 1.40 in the round-edged IOL group (P<.001). The sharp-edged IOL group had less peripheral fibrotic PCO. There was no significant difference between the 2 IOL groups in patient reports of edge glare.

CONCLUSION: The sharp-edged design of the ClariFlex OptiEdge silicone IOL led to significantly less PCO than the round-edged PhacoFlex SI-40 IOL 1 year postoperatively.

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Effect of accommodation and pupil size on the movement of a posterior chamber lens in the phakic eye.

Ophthalmology, 2004; 325-31

PURPOSE: Although a posterior chamber phakic intraocular lens provides effective refractive correction of high myopia and hyperopia, mechanical contact between the implantable contact lens (ICL) and the crystalline lens and inadequate aqueous circulation in the prelenticular space could cause subcapsular opacification. To assess whether and to what extent such mechanical contact occurs, changes in the distance between the STAAR Collamer ICL and the crystalline lens under various conditions were investigated.

DESIGN: Open pilot study.

PARTICIPANTS: Thirteen eyes of 11 myopic and 2 hyperopic patients with a mean age of 38 years (range, 19-53 years) were examined at least 6 months after ICL implantation.

METHODS: A noninvasive, high-resolution biometry technique, partial coherence interferometry, was used to measure distance changes between the ICL and the crystalline lens during subjective accommodation, after instillation of pilocarpine, and under changing light conditions.

MAIN OUTCOME MEASURES: Mean distance changes from the posterior corneal surface to the ICL, from the posterior corneal surface to the anterior surface of the crystalline lens, and the distance between the ICL and the crystalline lens.

RESULTS: In the nonaccommodated state, the mean distance between the ICL and the crystalline lens was 457 microm (range, 123-924 microm). During subjective accommodation, a significant (P<0.01) decrease and, after topical application of pilocarpine, a nonsignificant (P=0.35) decrease of anterior chamber depth was accompanied by a nonsignificant (P = 0.71) reduction of the ICL-crystalline lens distance. Under photopic conditions, a significant mean reduction (P<0.01) of the ICL-crystalline lens distance of -28 microm (range, -16 to -188 microm) was observed.

CONCLUSIONS: Partial coherence interferometry biometry enabled noninvasive high-precision investigation of ICL dynamics. No significant changes between the ICL and the crystalline lens were detected during subjective accommodation and after application of pilocarpine. However, under photopic conditions, with constriction of the pupil, the distance between the ICL and the crystalline lens was significantly reduced. This mechanism might cause inadequate aqueous circulation in the prelenticular space and might be one of the causes of subcapsular opacification in some of the eyes after ICL implantation.

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Effect of an acrylic intraocular lens with a sharp posterior optic edge on posterior capsule opacification.

J Cataract Refract Surg, 2002; 1105-11

PURPOSE: To compare the posterior capsule opacification (PCO) inhibiting effect of the sharp posterior optic edge design of the Sensar OptiEdge AR40e intraocular lens (IOL) (Allergan Surgical) with that of the round-edged design of the Sensar AR40 IOL. Setting Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This prospective randomized patient- and examiner-masked study comprised 106 eyes of 53 patients with bilateral age-related cataract. Each patient had cataract surgery in both eyes and received an AR40 IOL in 1 eye and an AR40e IOL in the other eye. Postoperative examinations were at 1 week, 2 and 6 months, and 1 year. Digital slitlamp and digital retroillumination images of each eye were taken. The amount of PCO was assessed subjectively at the slitlamp and objectively using automated image-analysis software.

RESULTS: The AR40e group had significantly less regeneratory and fibrotic PCO 1 year after surgery. The mean automated image-analysis software PCO score (scale 0 to 10) was 2.19 in the AR40 group and 1.10 in the AR40e group (P <.001). The AR40e group had less peripheral fibrotic PCO. There was no significant difference in patient-reported edge glare between the 2 IOL groups.

CONCLUSIONS: The sharp-edged design of the Sensar OptiEdge AR40e IOL led to significantly less PCO than the round-edged AR40 IOL 1 year postoperatively.

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Effect of an aspheric intraocular lens on the ocular wave-front adjusted for pupil size and capsulorhexis size.

Acta Ophthalmol, 2014; e353-7

PURPOSE: To compare the ocular wave-front of eyes with silicone Intraocular lens (IOLs) with aspheric and spherical optics after cataract surgery, taking into account the patient's pupil size under reading conditions and after pupil dilatation.

METHODS: In this institutional prospective, randomized, controlled, patient and examiner masked, bilateral trial with intra-individual comparison, 60 eyes of 30 patients with bilateral age-related cataract were included. Each patient received a spherical IOL (CeeOn Edge, 911A, AMO, Santa Ana, CA, USA) in one eye and an aspheric IOL (Tecnis, Z9000, AMO) in the contra-lateral eye. Exclusion criteria were other ocular pathologies, capsular changes or zonular weakness. The main outcome variable was spherical aberration of the ocular wave-front under mesopic pupil conditions measured 2 years after surgery. Additional outcome variables were visual acuity and photopic and mesopic contrast sensitivity.

RESULTS: There was no significant difference in visual acuity between the two IOL types under physiological pupil conditions and also not after pupil dilation. However, spherical aberrations were significantly lower with the aspheric IOL (SA: spherical 0.38 μm, SD: 0.11 μm; aspheric 0.10 μm, SD: 0.13 μm; p < 0.01), and there was a significant difference in contrast sensitivity at 12 cycles/degree.

CONCLUSIONS: This is the first randomized and masked trial on visual function and ocular wave-front after implantation with this silicone aspheric IOL, taking the patients' own pupil size into account. The effect on visual function was detectable for mesopic contrast sensitivity, but there was no difference in visual acuity. The SA was found to be significantly lower under physiological pupil conditions as well as when recalculated for the rhexis size and under pharmacological dilatation.

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Effect of anterior capsule polishing on fibrotic capsule opacification: three-year results.

J Cataract Refract Surg, 2004; 2322-7

PURPOSE: To evaluate the long-term effect of anterior capsule polishing on anterior capsule opacification (ACO) and peripheral fibrotic posterior capsule opacification (PCO).

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: This randomized double-blind study comprised 104 eyes of 52 patients with bilateral age-related cataract. All patients received round-edged intraocular lenses (IOLs); 26 received an SI-40 IOL (Advanced Medical Optics Inc.) in both eyes, and 26 received a Silens6 IOL (Domilens) in both eyes. Both IOLs consist of different silicone material and have different haptic angulation. The SI-40 IOL has 13.0 mm open-loop poly(methyl methacrylate) (PMMA) haptics angulated by 10 degrees. The Silens6 IOL has 12.5 mm open-loop PMMA haptics with no angulation. In 1 eye, the anterior capsule was extensively polished. The anterior capsule was left unpolished in the contralateral eye, which acted as a control. Digital slitlamp photographs of the ACO and fibrotic PCO were taken with a standardized technique for 3 years postoperatively. The intensity of ACO was measured objectively (score 0% to 100%) using Adobe Photoshop software. Fibrotic PCO was graded subjectively (score 0 to 4).

RESULTS: The mean ACO was 17% in the polished eyes and 26% in the control eyes (P = .0001). The mean fibrotic PCO score was 0.5 and 1.0, respectively (P = .0007). The mean ACO was 15% in the polished SI-40 eyes and 26% in the control SI-40 eyes (P = .01). It was 19% in the polished Silens6 eyes and 26% in the control Silens6 eyes (P = .003). The mean fibrotic PCO score was 0.4 in the polished SI-40 eyes and 1.1 in the control SI-40 eyes (P = .0006). It was 0.6 in the polished Silens6 eyes and 0.9 in the control Silens6 eyes (P = .08).

CONCLUSIONS: Three years after surgery, eyes in which the anterior capsule was extensively polished had less ACO and fibrotic PCO with both round-edged silicone IOLs. In eyes with Silens6 IOLs, however, the reduction in fibrotic PCO was not significant.

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Effect of anterior capsule polishing on posterior capsule opacification and neodymium:YAG capsulotomy rates: three-year randomized trial.

J Cataract Refract Surg, 2005; 2067-75

PURPOSE: To compare the long-term effect of extensive polishing and nonpolishing of the anterior lens capsule on posterior capsule opacification (PCO) and neodymium:YAG (Nd:YAG) capsulotomy rates.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: This prospective randomized bilateral double-masked study included 108 eyes of 54 consecutive patients with age-related cataract. Following phacoemulsification, 3-piece intraocular lenses (IOLs) with round-edged silicone optics were implanted. Patients received an Allergan SI-40 IOL with a truncated, round optic edge or a Domilens Silens6 IOL with a fully round optic edge. Patients were randomly assigned to have extensive anterior capsule polishing with the Menapace aspiration curette or no treatment in the first eye; the second eye received the opposite treatment. Digital retroillumination images were taken at 1 week, 1 year, and 3 years, and Nd:YAG capsulotomy rates were evaluated. Posterior capsule opacification was objectively scored using automated image analysis software (AQUA) or estimated based on clearly defined assumptions if a capsulotomy had been performed.

RESULTS: Thirty-nine patients (78 eyes) concluded the study. Three-year PCO scores after polishing did not differ significantly (P>.05). However, 21 polished eyes (53.8%) required Nd:YAG laser capsulotomy compared with 14 nonpolished eyes (35.9%). The mismatch between PCO scores and Nd:YAG rates resulted from a change in PCO morphology that is not detected by scoring methods based on retroillumination photography but is visually disturbing to patients.

CONCLUSIONS: Polishing the anterior capsule was effective in reducing fibrotic opacification but ineffective in reducing regeneratory opacification. Changes in regeneratory PCO morphology not picked up by retroillumination photography increased the need for Nd:YAG laser capsulotomy.

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Effect of anterior capsule polishing on the posterior capsule opacification-inhibiting properties of a sharp-edged, 3-piece, silicone intraocular lens: three- and 5-year results of a randomized trial.

J Cataract Refract Surg, 2006; 1513-20

PURPOSE: To evaluate the long-term effects of anterior capsule polishing on regeneratory posterior capsule opacification (PCO), anterior capsule opacification (ACO), and fibrotic PCO with a silicone intraocular lens (IOL) with sharp optic edges.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: This prospective bilateral randomized patient- and examiner-masked clinical trial comprised 130 eyes of 65 patients with bilateral age-related cataract. All eyes had implantation of a 3-piece silicone IOL with a truncated, sharp-edged optic (CeeOn Edge 911A, Advanced Medical Optics). In 1 eye, the anterior capsule was extensively polished using an aspiration curette after phacoemulsification and cortex aspiration. Regenerative PCO was quantified objectively, while ACO and fibrotic PCO were graded subjectively 1, 2, 3, and 5 years postoperatively.

RESULTS: The mean ACO score was significantly lower in the eyes in which the anterior capsule had been polished (1 year, P<.02; 2 years, P<.03; 3 years, P<.01; 5 years, P<.01). The mean difference in regeneratory PCO and fibrotic PCO scores between the 2 groups was not statistically significant.

CONCLUSIONS: Three years after cataract surgery, eyes in which the anterior capsule had been polished had significantly less ACO. However, polishing did not lower PCO intensity when a sharp-edged CeeOn 911A IOL was implanted in the bag. Although results indicate that anterior capsule polishing may enhance the development of regeneratory PCO, this trend did not reach statistical significance.

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Effect of cooled intraocular irrigating solution on the blood-aqueous barrier after cataract surgery.

J Cataract Refract Surg, 1999; 566-8

PURPOSE: To evaluate the effect of cooled intraocular irrigating solution during phacoemulsification on postoperative blood-aqueous barrier (BAB) disturbance.

SETTING: Department of Ophthalmology, University of Vienna, Austria.

METHODS: In a prospective, randomized clinical study, 40 eyes with senile cataract had phacoemulsification with irrigating solutions cooled to approximately 10 degrees C (n = 20) or at room temperature (n = 20). Surgical procedure and postoperative therapy were otherwise identical in both groups. Postoperative BAB disturbance was assessed with the laser flare-cell meter on days 1, 3, 7, 14, and 28.

RESULTS: Anterior chamber flare was significantly lower in the group with cooled irrigating solution on postoperative day 1. There was no significant between-group difference in flare on any other postoperative day.

CONCLUSION: Cooled intraocular irrigating solution reduced immediate postoperative inflammation compared with irrigating solution at room temperature. However, this effect was of short duration.

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Effect of dorzolamide and latanoprost on intraocular pressure after small incision cataract surgery.

J Cataract Refract Surg, 1999; 1624-9

PURPOSE: To evaluate the effect of dorzolamide 2% and latanoprost 0.005% on intraocular pressure (IOP) after small incision cataract surgery.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This prospective study comprised 102 eyes of 102 consecutive patients scheduled for small incision cataract surgery. The patients were assigned preoperatively to 1 of 3 groups of 34 each: dorzolamide, latanoprost, and control (no treatment). One drop of the assigned medication was instilled immediately after surgery. Intraocular pressure was measured preoperatively and 6 and 20 to 24 hours postoperatively.

RESULTS: Six hours after surgery, the mean increase in IOP was 1.9 mm Hg +/- 3.9 (SD) in the dorzolamide group (P = .004 versus control), 2.2 +/- 3.0 mm Hg in the latanoprost group (P = .005 versus control), and 4.8 +/- 5.2 mm Hg in the control group. Twenty to 24 hours postoperatively, IOP decreased a mean of -0.9 +/- 3.5 mm Hg in the dorzolamide group (P = .012 versus control) and increased a mean of 0.3 +/- 3.6 mm Hg in the latanoprost group (P = 0.24 versus control) and 1.3 +/- 4.2 mm Hg in the control group. One eye in the dorzolamide group, 1 eye in the latanoprost group, and 4 eyes in the control group had an IOP of 30 mm Hg or higher 6 hours postoperatively.

CONCLUSION: Six hours postoperatively, dorzolamide and latanoprost were effective in reducing the IOP increase after small incision cataract surgery; however, at 20 to 24 hours, only dorzolamide was effective. Neither drug prevented IOP spikes of 30 mm Hg or higher.

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Effect of dorzolamide hydrochloride on central corneal thickness in humans with cornea guttata.

Arch. Ophthalmol., 2007; 1345-50

OBJECTIVE: To investigate the effect of dorzolamide hydrochloride on central corneal thickness in humans with cornea guttata.

DESIGN: Randomized, placebo-controlled, double-masked, 2-drug crossover study with 10 patients with cornea guttata and 10 healthy controls, who had mean endothelial cell counts of 988 and 2377 cells/mm(2), respectively. Study medications were 2% dorzolamide and placebo drops applied 3 times a day for 4 weeks. Central corneal thickness measurements using ACMaster (Carl Zeiss Meditec AG, Jena, Germany) and Goldmann applanation tonometry were performed at baseline, 1 day, 1 week, and 4 weeks.

RESULTS: The mean increases in central corneal thickness after 4 weeks in eyes with cornea guttata treated with dorzolamide and placebo were 26.3 microm (95% confidence interval, 8.8 to 43.7) and 3.3 microm (95% confidence interval, -0.5 to 7.1), respectively. No statistically significant changes were measured in the healthy control group. Dorzolamide caused a significant decrease in intraocular pressure (P < .01) while placebo did not cause significant changes (P = .50).

CONCLUSION: Application of dorzolamide for 4 weeks resulted in a statistically significant increase in central corneal thickness in patients with compromised corneal endothelium. These results indicate that patients with corneal endothelial problems receiving dorzolamide therapy should be monitored.

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Effect of endothelin and BQ123 on ocular blood flow parameters in healthy subjects.

Invest. Ophthalmol. Vis. Sci., 2001; 2949-56

PURPOSE: To characterize the role of the endothelin system in the blood flow control of the optic nerve head and of the choroid in humans.

METHODS: Two studies were performed in healthy subjects. Study 1 was a randomized, placebo-controlled, double-masked, balanced, two-way crossover design and study 2 a three way-way crossover design. In study 1 twelve healthy male subjects received endothelin (ET)-1 in stepwise increasing doses of 1.25, 2.5, and 5 ng/kg x min (each infusion step occurred over 20 minutes) coinfused with BQ123 (60 microg/kg x min) or placebo on two different study days. In study 2 twelve healthy male subjects received two doses of BQ123 (60 or 120 microg/kg x min over 60 minutes) or placebo on three different study days. Measurements of optic nerve head blood flow (ONHBF) and choroidal blood flow (ChBF) were performed with laser Doppler flowmetry in both studies. In study 2 mean flow velocity (MFV) of the ophthalmic artery was assessed with Doppler sonography.

RESULTS: In study 1, ET-1 significantly decreased ONHBF (-22.8% +/- 4.3% at 5 ng/kg x min, P = 0.003 versus baseline) and ChBF (-21.7% +/- 3.2% at 5 ng/kg x min, P = 0.0001 versus baseline). The effect of the highest administered dose of exogenous ET-1 on ONHBF was significantly attenuated (P = 0.04, ANOVA) by coinfusion of BQ123. Effects of exogenous ET-1 on blood flow (2.5 ng/kg x min ET-1 or higher) also were attenuated in the choroid by coinfusion of BQ123 (ChBF: P = 0.03, ANOVA). In study 2, both dosages of BQ123 significantly increased MFV in the ophthalmic artery (60 microg/kg x min, 12.5% +/- 7.3%; 120 microg/kg x min, 17.2% +/- 9.2%, versus baseline; P = 0.001), but did not change blood flow in the ONH or the choroid.

CONCLUSIONS: BQ123 antagonizes the effects of exogenously administered ET-1 on blood flow in the ONH and the choroid. The data indicate, however, that ET-1 does not substantially contribute to the regulation of basal vascular tone in these tissues.

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Effect of fluorescein dye staining of the tear film on Scheimpflug measurements of central corneal thickness.

Cornea, 2012; 18-20

PURPOSE: To assess whether fluorescein dye in the tear film results in a clinically relevant change in central corneal thickness (CCT), as measured with Scheimpflug imaging (Pentacam HR; Oculus, Wetzlar, Germany). The study was conducted at Moorfields Eye Hospital NHS Foundation Trust.

METHODS: In this prospective, randomized, controlled, single-center study on healthy volunteers, CCT was measured using rotating Scheimpflug imaging and partial coherence interferometry technique. After 3 baseline measurements of both eyes, a drop of 0.25% fluorescein with 0.5% proxymetacaine hydrochloride dye, as used for measuring intraocular pressure with applanation Goldmann tonometry, was instilled in the first eye and measurements were repeated after 1 minute and 5, 10, 20, 40, and 60 minutes. A fluorescein drop was then instilled in the second eye, and 1 measurement was performed after 1 minute. Immediately afterwards, the second eye was rinsed with 2 ml of balanced saline solution and the CCT measurement was repeated. On a different day, a Schirmer II test was performed.

RESULTS: Thirty eyes of 15 volunteers were included in this study. The average CCT measured with Scheimpflug imaging was 539.1 μm (SD, 32.2 μm), and after instilling fluorescein, CCT values increased by 46.6 μm (SD, 11.4 μm; P < 0.01, paired t test). In 10 of 15 subjects, the fluorescein layer was still present 40 minutes after instilling the drop. Rinsing the eye decreased the fluorescein layer by 49.6% and a value of 24.8 μm (SD, 16.8 μm).

CONCLUSIONS: Because CCT measurements are critical for corneal refractive surgery, Scheimpflug imaging should not be performed after use of fluorescein dye for staining of the corneal epithelium or for applanation tonometry.

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Effect of haptic design on change in axial lens position after cataract surgery.

J Cataract Refract Surg, 2004; 45-51

PURPOSE: To compare the postoperative changes in anterior chamber depth (ACD) between single-piece and multipiece AcrySof intraocular lenses (IOLs) (Alcon Laboratories, Inc.) and their effect on the postoperative refractive shift.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This prospective randomized bilateral study with intraindividual comparison comprised 104 eyes of 52 consecutive patients with age-related cataract. All patients had standardized cataract surgery with a temporal self-sealing incision, phacoemulsification, and IOL implantation in the capsular bag. The first 30 patients received a single-piece, 5.5 mm optic IOL (AcrySof SA30) in 1 eye and a multipiece IOL (AcrySof MA30) in the other eye. Another 22 patients received the corresponding 6.0 mm optic models (AcrySof SA60 and AcrySof MA60, respectively). Anterior chamber depth measurements and evaluation of the change in ACD during the first 6 postoperative months were performed using partial coherence laser interferometry. The amount of change in capsulorhexis size during the first 6 postoperative months was assessed using standardized retroillumination photographs.

RESULTS: Single-piece IOLs shifted significantly less postoperatively than multipiece IOLs. The multipiece IOLs shifted forward, especially from 1 day to 1 month. The change in the capsulorhexis area was similar between IOL types.

CONCLUSIONS: Single-piece AcrySof IOLs shifted minimally after the first postoperative day; therefore, the prescription for spectacles in eyes with this IOL can be obtained soon after surgery.

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Effect of heparin coating of a foldable intraocular lens on inflammation and capsular bag performance after cataract surgery.

J Cataract Refract Surg, 2013; 1810-7

PURPOSE: To evaluate the effect of a heparin-coated foldable intraocular lens (IOL) on postoperative flare in high-risk patients.

SETTING: Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

DESIGN: Randomized clinical trial.

METHODS: This study included patients with diabetes mellitus (DM), pseudoexfoliation syndrome (PXF), or both scheduled for cataract surgery in both eyes. One eye received a coated IOL (Polylens EC-1YH PAL) and the other eye, an uncoated control IOL (Polylens EC-1Y PAL). Aqueous flare measurements were taken using a laser flare meter (FM-600, Kowa) preoperatively and 1 hour, 1 day, 3 weeks, and 3 months postoperatively. Visual acuity and anterior (ACO) and posterior (PCO) capsule opacification were assessed, and IOL centration and tilt were measured with a Purkinje meter.

RESULTS: Eighty eyes of 40 patients were included in the study; 64 eyes of 32 patients completed the study. The mean flare values (photons/ms) preoperatively and 1 hour, 1 day, 3 weeks, and 3 months postoperatively were 6.98 ± 3.71 (SD), 19.14 ± 18.90, 16.62 ± 25.33, 10.33 ± 9.70, 8.74 ± 4.64, respectively, with the coated IOL and 8.65 ± 5.73, 22.08 ± 16.23, 13.44 ± 13.71, 7.50 ± 4.11, and 7.03 ± 3.70, respectively, with the control IOL. No significant differences were found in flare, visual acuity, ACO, PCO, tilt, or centration between the coated IOL and the control IOL at any timepoint.

CONCLUSION: No significant differences in flare or capsule performance were found between the coated IOL and control IOL.

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The effect of inhalation of different mixtures of O2 and CO2 on ocular fundus pulsations.

Exp. Eye Res., 1996; 351-5

The effect of different mixtures of O2 and CO2 on pulsatile ocular blood flow as assessed by laserinterferometric measurement of fundus pulsations was studied. This was done in an effort to identify the gas mixture with an optimal O2/CO2 ratio for treatment in central retinal artery occlusion (CRAO). In a double-blind, randomized, placebo-controlled, six-way cross-over study, 20 healthy young subjects were studied. Fundus pulsation amplitude in the macula (FPAM) and in the optic disc (FPAO), arterialized capillary blood gases, and systemic haemodynamics were measured during baseline and 12 min inhalation periods of 100% O2, mixtures of 2.5%, 5%, 8%, 10% CO2 with oxygen, and air as placebo. The FPAM and FPAO decreased at 100% oxygen (FPAM: -6.2%, P < 0.01; FPAO: -15.1%. P < 0.001), but dose dependently increased with addition of CO2: whereas FPAM was not different versus placebo during inhalation of 2.5% CO2 with oxygen (+0.3%), addition of 5% CO2 and 8% CO2 to oxygen significantly increased FPAM versus placebo (+10.6%, P < 0.01 and +25.9%, P < 0.001, respectively), FPAO was slightly decreased by addition of 2.5% CO2 to oxygen (-2.6%, P < 0.05 versus placebo), 5% CO2 neutralized oxygen's effects on FPAO (+1.5%) and 8% CO2 + 92% O2 significantly increased FPAO (+16.0%, P < 0.001 versus placebo). Inhalation of 90% O2 + 10% CO2 was not tolerated by 19 subjects. Administration of 5% and 8% CO2 with oxygen significantly increased mean arterial pressure. We conclude that addition of 5% CO2 to oxygen is appropriate to maintain or even increase pulsatile ocular blood flow in the macula and optic disc at a level comparable to air-breathing. Addition of higher percentages of CO2 further increases fundus pulsations, with a very steep dose response relationship. Addition of 8% CO2 seems not applicable in patients due to pronounced systemic effects. Hence mixtures of 6 or 7% CO2 with oxygen should be used for further studies in patients with central retinal artery occlusion (CRAO).

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Effect of intraocular lens design on posterior capsule opacification.

J Cataract Refract Surg, 2008; 1976-85

Posterior capsule opacification (PCO) remains the most common long-term complication after cataract surgery. Many studies have attempted to identify factors that influence the development of PCO. The aim of this systematic review based on Cochrane methodology was to summarize the effects of intraocular lens (IOL) geometry, including modifications of the IOL optic (especially optic edge design) and haptics, on the development of PCO. Twenty-six prospective randomized controlled trials with a follow-up of at least 12 months were included. In 5 of 7 studies, visual acuity was better in sharp-edged IOLs than in round-edged IOL. The PCO score was significantly lower with sharp-edged IOLs but did not differ significantly between 1-piece and 3-piece open-loop IOLs. Because of the significant difference in the PCO score, sharp-edged IOL optics should be preferred to round-edged IOL optics.

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Effect of intraocular lens optic edge design and material on fibrotic capsule opacification and capsulorhexis contraction.

J Cataract Refract Surg, 2004; 1875-82

PURPOSE: To examine the influence of intraocular lens (IOL) optic edge design and optic material on fibrosis of the anterior and peripheral posterior capsules and on capsulorhexis contraction.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: This randomized controlled patient- and examiner-masked study comprised 210 eyes of 105 patients with bilateral age-related cataract. In Group 1 (n = 53), the Sensar OptiEdge AR40e hydrophobic acrylic IOL with a sharp posterior optic edge was compared with the AR40 acrylic IOL with a round edge. In Group 2 (n = 52), the ClariFlex OptiEdge silicone IOL with a sharp posterior optic edge was compared with the PhacoFlex SI-40 silicone IOL with a round edge All IOLs were manufactured by Advanced Medical Optics, Inc. Standardized digital slitlamp images of anterior capsule opacification (ACO) and fibrotic posterior capsule opacification (PCO) were taken 1 year postoperatively, and digital retroillumination images were taken at 1 week and 1 year. The intensity of fibrotic PCO was graded subjectively (score 0 to 4), ACO was graded objectively (score 0% to 100%), and the capsulorhexis area (mm(2)) was determined objectively.

RESULTS: One year after surgery, the mean ACO score was 32% in eyes with the sharp-edged acrylic IOL and 29% in eyes with the round-edged acrylic IOL (P<.05). In the silicone group, the mean was 31% and 26%, respectively (P<.05). The mean fibrotic PCO score was lower in eyes with a sharp-edged acrylic IOL than in eyes with a round-edged acrylic IOL (0.26 and 0.93, respectively; P<.05) and in eyes with a sharp-edged silicone IOL than in eyes with a round-edged silicone IOL (0.24 and 0.82, respectively; P<.001). At 1 year, the mean capsulorhexis area was statistically significantly smaller in eyes with a sharp-edged silicone IOL than in eyes with a round-edged silicone IOL (P<.05).

CONCLUSIONS: Acrylic and silicone IOLs with the sharp OptiEdge design led to significantly less fibrotic PCO but more ACO than round-edged acrylic and silicone IOLs. The sharp-edged silicone IOL caused significantly more capsulorhexis contraction than the round-edged silicone IOL and both acrylic IOLs.

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Effect of manual capsulorhexis size and position on intraocular lens tilt, centration, and axial position.

J Cataract Refract Surg, 2017; 902-908

PURPOSE: To evaluate the influence of a manual capsulorhexis size, shape, and position on postoperative axial position, tilt, and centration of intraocular lenses (IOLs).

SETTING: Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective cases series.

METHODS: Patients had cataract surgery and had follow-ups 1 hour and 3 months after surgery. Postoperatively, patients were divided into 3 groups according to the capsulorhexis shape and size as follows: control, symmetrical capsulorhexis between 4.5 mm and 5.5 mm; small group, capsulorhexis smaller than 4.5 mm; and eccentric, all other capsulorhexes. At both follow-ups, a retroillumination image, partial coherence interferometry measurements, and Purkinje meter measurements were performed.

RESULTS: This study comprised 255 eyes. The mean postoperative absolute anterior chamber depth shift in the control, eccentric capsulorhexis, and small capsulorhexis groups was 0.31 mm ± 0.27 (SD), 0.36 ± 0.24 mm, and 0.26 ± 0.24 mm, respectively (P = .419). The mean tilt in the control, eccentric capsulorhexis, and small capsulorhexis groups was 4.08 ± 2.13 degrees, 3.66 ± 2.04 degrees, and 2.82 ± 1.67 degrees, respectively (P = .370), and the mean decentration was 0.38 ± 0.23 mm, 0.40 ± 0.21 mm, and 0.17 ± 0.08 mm, respectively (P = .027).

CONCLUSIONS: Capsulorhexis size and shape had little effect on the capsular bag performance of modern IOLs. Only eyes with a severely malformed capsulorhexis had a slightly decentered IOL.

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Effect of Nd:YAG capsulotomy on the morphology of surviving Elschnig pearls.

Br J Ophthalmol, 2009; 1643-7

AIM: To observe the short-term changes in morphology of Elschnig pearls induced by Nd:YAG capsulotomy.

SETTING: Department of Ophthalmology, Medical University of Vienna, Austria

METHOD: Twenty eyes of 19 pseudophakic patients with regeneratory posterior capsule opacification (PCO) that were scheduled for YAG capsulotomy were included in this prospective study. High-resolution digital retroillumination images were taken 2 weeks, 1 week and shortly before and immediately, 1 week and 2 weeks after Nd:YAG capsulotomy. The series of images were analysed using a dedicated image analysing software (PearlTracer).

RESULTS: In total, 2431 Elschnig pearls were observed over the time-course of 4 weeks in this study. Of these, 535 pearls (30.6%) disappeared, and 503 pearls (27.6%) survived on the remaining capsule peripheral to the capsulotomy opening. The surviving pearls showed a significant decrease in size (20%) from immediately before to 10 min after capsulotomy. Within the first weeks after capsulotomy, there was a high number of newly appearing pearls, with 26% of all pearls being new between 1 and 2 weeks indicating high pearl turnover.

CONCLUSION: Capsulotomy had an immediate impact on the morphology of PCO outside the capsulotomy opening, probably due to the direct mechanical impact of the laser shockwave.

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Effect of optic edge design and haptic angulation on postoperative intraocular lens position change.

J Cataract Refract Surg, 2004; 52-7

PURPOSE: To assess the effect of optic edge design and optic-haptic angulation of open-loop intraocular lenses (IOLs) on postoperative axial movement and the final position of the optic by measuring the anterior chamber depth (ACD) during the first postoperative year using partial coherence interferometry (PCI).

SETTING: Department of Ophthalmology, Vienna General Hospital, Institute of Medical Physics, University of Vienna, Vienna, Austria.

METHODS: In study 1, a 3-piece silicone IOL with nonangulated modified C-loop haptics (MicroSil, Dr. Schmidt) was implanted in 78 eyes of 39 patients; patients were randomized to receive a round-edged optic IOL in 1 eye and a sharp-edged optic IOL in the other eye. The ACD was measured by PCI 1 day, 1 week, 3 months, and 1 year after surgery. In study 2, a foldable, 3-piece acrylic IOL with modified 10-degree angulated J-loop haptics (AcrySof MA60BM, Alcon) was implanted in 32 eyes of 32 patients. The ACD was measured by PCI 1 day, 1 week, and 3 months after surgery.

RESULTS: In eyes with a nonangulated silicone IOL, there was a significant postoperative change in ACD with both sharp-edged and round-edged designs (P<.01). There was forward movement of both IOL designs in the first week, with no significant difference between the 2 models. From 1 week to 3 months, there was backward movement of IOLs of both designs, with the sharp-edged IOL moving a significantly greater amount (P<.001). From 3 months to 1 year, IOLs with both optic edge designs moved slightly backward. Sixty-six percent of angulated IOLs showed continuous but variable forward movement and 34%, backward movement.

CONCLUSIONS: Optic edge design influenced postoperative axial optic movement and thus had an impact on the development of postoperative refraction (refractive shift, deviation from target refraction). The influence of optic-haptic angulation proved to be significantly greater and more variable than edge design.

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Effect of optic material and haptic design on anterior capsule opacification and capsulorrhexis contraction.

Am. J. Ophthalmol., 2006; 488-493

PURPOSE: To examine the influence of optic material (silicone and hydrophobic acrylic) and haptic design (one-piece and three-piece open loop) of sharp optic edge intraocular lenses (IOL) on anterior capsule opacification (ACO) and capsulorrhexis contraction.

DESIGN: Randomized, controlled, double-blind clinical trial with intraindividual comparison.

METHODS: This study was performed at the Department of Ophthalmology, Medical University of Vienna, Austria, and comprised 210 eyes of 105 patients with bilateral age-related cataract. In group 1 (n = 53 patients), a three-piece acrylic IOL was compared with a three-piece silicone IOL. In group 2 (n = 52 patients), the three-piece acrylic IOL was compared with the one-piece acrylic IOL. One year after the operation, standardized digital slit-lamp images of ACO were taken; 1 week and 1 year after the operation, digital retroillumination images were taken to assess capsulorrhexis size. The intensity of ACO was graded objectively (score, 0% to 100%), and the capsulorrhexis area (square millimeters) was determined objectively.

RESULTS: One year after surgery, the mean ACO score was 21% for the acrylic and 20% for the silicone IOL (P = .4) in group 1 and 18% for both the three-piece and one-piece acrylic IOLs (P = .87) in group 2. Concerning the amount of capsulorrhexis contraction, there was no significant difference between the IOL types that were evaluated in this study (after Bonferroni-Holm correction, P > .05).

CONCLUSION: In the hydrophobic sharp optic edge IOLs that were examined, neither the optic material nor the haptic design had an influence on the amount of ACO or capsulorrhexis contraction.

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Effect of optic material on posterior capsule opacification in intraocular lenses with sharp-edge optics: randomized clinical trial.

Ophthalmology, 2005; 67-72

PURPOSE: Comparison of the intensity of posterior capsule opacification (PCO) between a silicone intraocular lens (IOL) and a hydrophobic acrylic IOL, both of them 3-piece and open-loop and having truncated optics with sharp edges.

DESIGN: Randomized, controlled, patient- and examiner-masked trial with intrapatient comparison.

PARTICIPANTS AND CONTROLS: One hundred six eyes of 53 patients with age-related bilateral cataract.

METHODS: Each patient had cataract surgery in both eyes and received a silicone IOL in one eye and a hydrophobic acrylic IOL in the fellow eye. Follow-up examinations were at 1 and 3 years after surgery. The patients were examined at the slit lamp, visual acuity (VA) was assessed, and standardized high-resolution digital retroillumination images of the posterior capsule were taken. The amount of PCO was assessed subjectively at the slit lamp and objectively using automated image analysis software. Data of 56 eyes of 28 patients, who were examined at each follow-up, were analyzed.

MAIN OUTCOME MEASURE: Posterior capsule opacification intensity at 3 years as measured with automated image analysis.

RESULTS: At 1 and 3 years after surgery, PCO did not differ between the silicone (1.6 and 1.9 [image analysis scores, 0-10 scale], respectively) and acrylic IOLs (1.7 and 2.2) (P > 0.24). Furthermore, there was no significant difference in best-corrected VA, rhexis/IOL overlap, capsular folds, and amount of anterior capsule opacification during the follow-up period. In each group, one neodymium:yttrium-aluminum-garnet (YAG) laser capsulotomy was performed during the entire study duration.

CONCLUSION: Silicone and hydrophobic acrylic are similarly effective in inducing the PCO-inhibiting effect of a rectangular, sharp optic edge. Three years after surgery, the PCO intensity and the YAG rate were low with both IOL models.

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Effect of patient motivation on near vision in pseudophakic patients.

Am. J. Ophthalmol., 2009; 398-405.e3

PURPOSE: To investigate the effect of 'training' the patients' near vision and motivating them towards a spectacle-independent outcome on near vision performance in pseudophakic patients with standard intraocular lens (IOL).

DESIGN: Prospective randomized, controlled, examiner-masked clinical trial.

METHODS: Eighty eyes of 40 patients with standard cataract surgery were randomly assigned to a "motivated" or "control" group. In the motivated group, subjects were told that they are taking part in a special protocol to improve their near-reading ability after cataract surgery and were instructed not to use reading glasses for at least three months and received cycloplegic eye drops for 10 days after surgery. Follow-up examinations at three months included best-corrected distance visual acuity (VA), distance-corrected near VA, best-corrected near VA, assessment of the defocus curve, and reading speed, as well as pilocarpine-, cyclopentolate- and nearpoint-induced IOL shift assessed with partial coherence interferometry. Additionally, a questionnaire evaluating patients' postoperative satisfaction, independency of reading glasses, and daily-life performance without glasses was carried out three months and one year postoperatively.

RESULTS: No difference in reading ability and IOL shift between "motivated" and "control" patients could be detected. However, the motivated patients were less dependent on reading glasses and their ability to be able to perform activities of daily life without glasses was significantly better.

CONCLUSION: There was no improvement of ciliary body function in pseudophakic patients with a special training protocol. However, near vision training made patients more independent of reading glasses.

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Effect of posterior capsule opacification on macular sensitivity.

J Cataract Refract Surg, 2008; 52-6

PURPOSE: To evaluate the effect of posterior capsule opacification (PCO) on macular sensitivity.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: Macular sensitivity, best corrected visual acuity (BCVA), and PCO intensity were evaluated before and after neodymium:YAG (Nd:YAG) laser capsulotomy in pseudophakic eyes with clinically significant PCO that had a healthy macula or dry age-related macular degeneration (ARMD). Macular sensitivity was determined using the fundus-related Microperimeter 1 (Nidek) in a central field of 10 degrees. The intensity of the PCO was assessed objectively in the central 3.0 mm area (score 0 to 10) using quantification software.

RESULTS: After Nd:YAG capsulotomy, both groups had a significant improvement in BCVA and mean macular sensitivity; the change in the mean logMAR value was -0.26 in the healthy macula group and -0.23 in the dry ARMD group and the change in mean macular sensitivity, 2.5 dB and 2.0 dB, respectively. Before Nd:YAG capsulotomy, significant correlations were observed between PCO values, BCVA, and macular sensitivity in the healthy macula group only (P<.01).

CONCLUSIONS: Neodymium:YAG laser capsulotomy improved BCVA and macular sensitivity. The PCO scores correlated well with the PCO-induced decrease in BCVA and with PCO-induced loss of macular sensitivity. Functional macular mapping indicated an overall loss of macular sensitivity in patients with dry ARMD. There was no significant association between PCO values and macular sensitivity in eyes with dry ARMD.

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Effect of small incision cataract surgery on ocular blood flow in cataract patients.

J Cataract Refract Surg, 1999; 964-8

PURPOSE: To evaluate the effect of small incision cataract surgery using peribulbar anesthesia on ocular blood flow in patients with senile cataract.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: In 33 eyes of 33 consecutive patients scheduled for cataract surgery, ocular hemodynamics were measured preoperatively and 1 day, 1 week, and 1 month postoperatively. Measurements included fundus pulsation amplitude (FPA) with a laser interferometric method that assessed the pulsatile choroidal blood flow, mean blood flow velocity (MFV), and resistive index (RI) in the ophthalmic artery (OA) and the central retinal artery (CRA) with Doppler sonography. Systemic hemodynamics and intraocular pressure (IOP) also were measured.

RESULTS: The FPA, MFV, and RI in the OA and the CRA did not change postoperatively from baseline values. Systemic hemodynamics, IOP, and as a consequence ocular perfusion pressure, also remained unchanged.

CONCLUSION: Uneventful small incision cataract surgery using peribulbar anesthesia did not affect ocular blood flow in patients with senile cataract between 1 day and 1 month postoperatively.

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The effect of systemic nitric oxide-synthase inhibition on ocular fundus pulsations in man.

Exp. Eye Res., 1997; 305-12

There is experimental evidence that endothelium derived nitric oxide is involved in the regulation of ocular vascular tone. The purpose of this study was to investigate the effects of NO-synthase inhibition by N-monomethyl-L-arginine (L-NMMA) on ocular fundus pulsations in young healthy volunteers. Three milligrams per kilograms L-NMMA were administered i.v. over 5 minutes. Protocol 1: Measurements of blood pressure, pulse rate, fundus pulsation amplitude, NO-exhalation, and cardiac output were performed at baseline and 10, 30, 60, 90, 150, and 300 minutes after L-NMMA infusion (n = 8). Fundus pulsation amplitude, which has been shown to estimate the pulsatile component of the choroidal blood flow, was recorded with a recently developed laser interferometer. Protocol 2: Measurements of blood pressure, pulse rate, fundus pulsation amplitude, NO-exhalation, and blood flow velocity in the ophthalmic artery were performed in a randomized, placebo controlled cross over study (n = 10). Ten minutes after L-NMMA administration fundus pulsation amplitude decreased by 23 +/- 2% (protocol 1) and 19 +/- 1% (protocol 2, P < 0.01 each), cardiac output by 12 +/- 2% (P < 0.01), and exhaled NO by 55 +/- 6% (protocol 1) and 41 +/- 6% (protocol 2, P < 0.01 each). All parameters returned to baseline values within the 300 minutes observation period, with a faster recovery of fundus pulsation amplitude than of cardiac output and exhaled NO. Blood pressure, pulse rate, and ophthalmic artery blood flow velocity showed only minor changes during and after administration of L-NMMA. Our results suggest that systemic NO-synthase inhibition reduces pulsatile choroidal and most likely total choroidal blood flow in humans. The recovery of vascular tone in choroidal vessels seems to be different from the cardiovascular response. Our findings indicate that reduced fundus pulsations after L-NMMA are caused by systemic factors as well as by local reactions of the choroidal vasculature.

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Effect of the hydrophilicity of acrylic intraocular lens material and haptic angulation on anterior capsule opacification.

Br J Ophthalmol, 2007; 476-80

AIM: To evaluate the influence of hydrophilic and hydrophobic acrylic material and haptic angulation on anterior capsule opacification (ACO).

METHODS: Prospective study on 53 patients with bilateral age-related cataract. Patients underwent standard cataract surgery by the same surgeon and randomly received a hydrophilic acrylic intraocular lens (IOL) in one eye and a hydrophobic acrylic IOL in the other eye. Forty five of these patients completed the one-year follow-up. The following parameters were assessed: decentration, buttonholing, anterolenticular gap (ALG), ACO, outgrowth and refractive outcome.

RESULTS: At the one-year follow-up, ACO was seen in 80% of the hydrophilic and 100% of the hydrophobic IOLs. ACO was more intense in the hydrophobic IOLs (p<0.001). Outgrowth was seen in 42% of the hydrophilic and 2% of the hydrophobic IOLs (p = 0.0003). No case of persisting ALG was seen in the hydrophobic IOLs, but in 42% of the hydrophilic IOLs. The refractive outcome was -0.29 (SD 0.56) dioptres for the hydrophilic and 0.003 (SD 0.44) dioptres for the hydrophobic IOLs (p<0.001).

CONCLUSION: These results suggest that there is less ACO in hydrophilic acrylic than in hydrophobic acrylic IOLs. Although material properties might play a role, the angulated haptics of the hydrophilic IOLs exert an additional effect by the persisting ALG and a lack of contact between the IOL and the anterior capsule.

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Effect of topical brimonidine on intraocular pressure after small incision cataract surgery.

J Cataract Refract Surg, 2001; 1227-31

PURPOSE: To evaluate the effect of brimonidine 0.2% on intraocular pressure (IOP) after small incision cataract surgery.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This prospective randomized study comprised 80 eyes of 40 patients scheduled for small incision cataract surgery in both eyes. In each patient, 1 eye was randomly assigned to receive 1 drop of brimonidine 0.2% or no treatment (control) immediately after surgery. The fellow eye received the other assigned treatment. All patients had standardized surgery by the same surgeon with sodium hyaluronate 1%, a temporal 3.5 mm sutureless posterior limbal incision, phacoemulsification, and implantation of a foldable intraocular lens. The IOP was measured preoperatively as well as 6 and 20 to 24 hours and 1 week postoperatively.

RESULTS: Six hours after surgery, the mean increase in IOP was 4.7 mm Hg +/- 6.1 (SD) in the brimonidine group and 4.6 +/- 5.3 mm Hg in the control group. In each group, 17 eyes (43%) had an IOP increase of 5 mm Hg or more. Twenty to 24 hours after surgery, the mean increase in IOP was 1.5 +/- 4.2 mm Hg in the brimonidine group and 1.6 +/- 4.4 mm Hg in the control group. There were no statistically significant between-group differences at any measurement.

CONCLUSIONS: In both groups, IOP significantly increased 6 hours and 20 to 24 hours after small incision cataract surgery. Brimonidine 0.2% failed to reduce the IOP increase observed after small incision cataract surgery.

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Effect of topical prednisolone and diclofenac on the short-term change in morphology of posterior capsular opacification.

Am. J. Ophthalmol., 2006; 550-6

PURPOSE: To observe and document the effect of steroidal and nonsteroidal antiinflammatory treatment on the formation of Elschnig pearls.

DESIGN: A prospective, randomized, double blinded, placebo controlled, two-way-cross-over study.

METHODS: Thirty-nine eyes of 32 patients with pronounced, regeneratory posterior capsule opacification (PCO) were included. The patients were treated topically with prednisolone and diclofenac (verum) or with lubricating eye drops (placebo) four times daily for one week. After a wash-out period of two weeks the patients received the contrary treatment also four times daily for one week. Digital retroillumination images were taken at day one, three, five, eight, and 15 of each medication period. The changes in the size of 4,675 Elschnig pearls were analyzed.

RESULTS: The mean cumulative area of all marked pearls/eye and follow-up was 1.2 mm(2) (range: 0.1 mm(2) to 3.2 mm(2)). The mean pearl size was 12,809 microm(2) (range: 60 microm(2) to 1.08 x 10(6) microm(2)). Between the follow-up examinations, 1,274 pearls disappeared (mean: 33 pearls/eye, range: five to 69 pearls; 27%) and 777 newly formed pearls appeared (mean: 20 pearls/eye, range: three to 53 pearls; 20%). There was no statistically significant difference in pearl size change and in number of disappeared and newly appeared pearls between the verum and the placebo treatments.

CONCLUSIONS: Topical prednisolone and diclofenac do not influence the short-term change of Elschnig pearls. Elschnig pearls disappear and appear within days. The degree of progression and regression varies greatly among eyes.

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Effect of trabeculectomy on ocular blood flow.

Br J Ophthalmol, 2005; 185-8

BACKGROUND/AIM: Current evidence suggests that vascular insufficiencies in the optic nerve head play an important part in the pathogenesis of glaucomatous optic neuropathy. Trabeculectomy is the most common operative procedure for the treatment of medically uncontrolled glaucoma. This study was conducted to investigate whether trabeculectomy may improve ocular haemodynamics.

METHODS: 30 patients with primary open angle glaucoma about to undergo trabeculectomy were included in the study. Patients were evaluated before surgery and at 2 and 10 weeks after trabeculectomy. Optic nerve head blood flow (OnhBF) was assessed with scanning laser Doppler flowmetry. Fundus pulsation amplitude (FPA) measurements were obtained with laser interferometry.

RESULTS: Because of the decrease in intraocular pressure there was a significant increase in ocular perfusion pressure (OPP) following trabeculectomy (18.5% (SD 12.0%) and 19.0% (17.1%) at 2 and 10 weeks postoperatively; p <0.001). A significant increase in OnhBF was observed after trabeculectomy (11.6% (16.4%) and 16.2% (20.2%) for each postoperative visit, respectively; p <0.001). FPA was also significantly higher compared with baseline values (17.2% (17.3%) and 17.4% (16.3%), respectively; p <0.001). A significant association between the increase in OPP and the increase in OnhBF and FPA was observed 10 weeks after surgery (r = 0.47; p = 0.009, and r = 0.50; p = 0.005, respectively).

CONCLUSION: The results of this study suggest that trabeculectomy improves ocular blood flow in patients with chronic open angle glaucoma.

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Effect of tropicamide on aqueous flare before and after cataract surgery.

J Cataract Refract Surg, 2000; 382-5

PURPOSE: To examine the effect of tropicamide on flare intensity under phakic and pseudophakic conditions and to differentiate between the possible mechanisms of action of tropicamide on aqueous flare.

SETTING: Department of Ophthalmology, Vienna General Hospital, University of Vienna, Vienna, Austria.

METHODS: In this prospective study, aqueous flare was measured with the laser flare-cell meter in 20 eyes of 20 patients with age-related cataract enrolled for cataract surgery. Measurements were performed before and 30, 90, and 180 minutes after pupil dilation with tropicamide 0.5%. This measurement was performed in the phakic eye on the day before surgery and in the pseudophakic eye on postoperative days 1, 3, 7, and 28.

RESULTS: After tropicamide instillation, aqueous flare decreased preoperatively and on all postoperative days. There was a continuous flare decrease until 3 hours after instillation, reaching a maximum decrease of about 30%. Pupil diameter reached its maximum after 30 minutes.

CONCLUSION: Tropicamide significantly decreased aqueous flare, seemingly by pharmacological means, not volumetric changes. The time between drug application and measurement should be kept constant.

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Effects of acetazolamide on choroidal blood flow.

Stroke, 1998; 997-1001

BACKGROUND AND PURPOSE: The acetazolamide provocation test is commonly used to study cerebrovascular vasomotor reactivity. On the basis of the effect of a carbonic anhydrase inhibitor in the central nervous system, we hypothesized that acetazolamide may also increase blood flow in the human choroid.

METHODS: In a placebo-controlled, randomized, double-blind, three-way crossover design, acetazolamide (500 mg or 1000 mg i.v.) or placebo was administered to nine healthy subjects. The effect of acetazolamide was studied at 15-minute intervals for 90 minutes. Pulsatile choroidal blood flow was assessed with laser interferometric measurement of fundus pulsation. In addition, mean blood flow velocity and resistive index in the ophthalmic artery were measured with Doppler sonography. In a second study in six healthy subjects, we assessed the effect of acetazolamide (1000 mg i.v.) on intraocular pressure.

RESULTS: Acetazolamide increased fundus pulsation amplitude in a dose-dependent manner (1000 mg: +33%; 500 mg: +20%; P<0.001, ANOVA). The effect of acetazolamide on MFV (1000 mg: +18%; 500 mg: +8%; P=0.003, ANOVA) and RI (1000 mg: -4%; 500 mg: -2%; P=0.006, ANOVA) was less pronounced but also significant. Acetazolamide did not induce any changes in systemic hemodynamic parameters but significantly decreased intraocular pressure (1000 mg: -37%; P<0.0001).

CONCLUSIONS: The present data show for the first time that intravenously administered acetazolamide increases choroidal blood flow in humans. This phenomenon therefore indicates that the acetazolamide provocation test may qualify as a tool to investigate ocular vasomotor reactivity in a variety of ocular diseases. Moreover, the increase in choroidal blood flow after carbonic anhydrase inhibition can be expected to contribute to the therapeutic efficacy of carbonic anhydrase inhibitors in glaucoma.

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The effects of acetazolamide on the electroretinographic responses in rats.

Invest. Ophthalmol. Vis. Sci., 1995; 1019-26

PURPOSE: To study the mechanisms and sites of action of the carbonic anhydrase inhibitor, acetazolamide (AZM), on the rod- and cone-mediated electroretinogram (ERG) of the dark-adapted rat.

METHODS: After a within-subjects design, ERG responses to brief, full-field flashes were recorded from adult (60 to 90 days old) albino rats, with and without AZM (5 mg/100 g, intraperitoneally). Flickering stimuli (6 and 26 Hz) were used to study rod- and cone-mediated responses. Aspartate-isolated responses of the isolated retina were recorded with and without AZM in the superfusate. The a-wave and PIII responses were fitted with a model of the rod's response by estimating the maximum response (Rmp3), sensitivity (S), and delay td. The b-wave response amplitude and implicit time were examined as a function of stimulus energy. The parameters obtained in the AZM-treated and untreated conditions were compared.

RESULTS: Acetazolamide causes a significant decrease in saturated rod response, b-wave amplitude, aspartate-isolated PIII, and the rod- and cone-mediated responses to flickering light. The estimated sensitivity of the rod response (S), b-wave sensitivity, and b-wave implicit time are not altered significantly by AZM.

CONCLUSION: Acetazolamide, probably through mechanisms that acidify the retina, attenuates the amplitudes of the retinal responses without significant effect on sensitivity.

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Effects of antiglaucoma drugs on ocular hemodynamics in healthy volunteers.

Clin. Pharmacol. Ther., 1997; 583-95

BACKGROUND AND PURPOSE: There is evidence that ocular blood flow plays a critical role in the clinical course of glaucoma. Hence a reduction in ocular blood flow due to topical antiglaucoma treatment should be avoided. The purpose of this study was to characterize the effect of antiglaucoma drugs on ocular hemodynamics.

METHODS: In a double-blind, placebo-controlled, randomized crossover study, we investigated the effects of single topical doses of five beta-blocking agents (befunolol, betaxolol, levobunolol, metipranolol, and timolol), two adrenergic agents (clonidine and dipivefrin [INN, dipivefrine]), and a parasympathomimetic agent (pilocarpine) on ocular and systemic hemodynamics in healthy subjects (n = 10). Fundus pulsation amplitudes in the macula and the optic disc were measured to characterize pulsatile choroidal and optic disc blood flow, respectively. Moreover, central retinal and ophthalmic artery blood flow velocities were measured by Doppler ultrasound.

RESULTS: Befunolol, metipranolol, timolol, clonidine, and dipivefrin reduced fundus pulsations in the macula and the optic disc (-9% to -14% versus baseline). In contrast, betaxolol, levobunolol, and pilocarpine had no effect on fundus pulsations. Antiglaucoma drugs had no effect on either blood flow velocities in the central retinal or the ophthalmic artery or systemic hemodynamics.

CONCLUSIONS: Our results indicate that befunolol, metipranolol, timolol, clonidine, and dipivefrin reduce choroidal and optic disc blood flow. This could be caused by drug diffusion to the choroid, which may cause vasoconstriction. Ocular blood flow reduction was not observed with betaxolol, levobunolol, or pilocarpine. The lack of effect of all drugs under study on central retinal blood flow velocity might partially be the result of autoregulative mechanisms. Because optic nerve head blood flow likely plays a critical role in the clinical course of glaucoma, the use of antiglaucoma drugs, which reduce blood flow, should be reconsidered.

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Effects of change in intraocular pressure on axial eye length and lens position.

Eye (Lond), 2008; 657-61

PURPOSE: To quantify the biometric changes of ocular dimensions with mechanical elevation of intraocular pressure (IOP) in vivo, to get a better understanding of the elastic properties of the human ocular structures that may play a role in the pathogenesis of various diseases such as myopia or glaucoma.

METHODS: Changes in IOP were induced by a suction cup in 18 eyes under cycloplegia. Axial eye length (AEL) and anterior chamber depth (ACD) were measured with non-invasive laser interferometry during elevation of the IOP 10 and 20 mmHg over baseline values and after a 10-min resting period.

RESULTS: IOP elevation of 10 and 20 mmHg respectively caused a significant increase of AEL of 23 mum (95% confidence interval: 14-34 microm) and 39 microm (confidence interval (CI): 28-51 microm). After mechanical oculopression, which resulted in an IOP reduction of -5.1 mmHg (CI: -6.3 to -4.0 mmHg) vsbaseline, a significant shortening of -7 microm (CI: -13 to 0 microm) was observed. The change in AEL correlated with the change in IOP (r=0.66, P=0.005). Furthermore, a significant increase in ACD of 30 microm (CI: 24-36 microm) was detected with IOP reduction after oculopression, but no change was seen during IOP elevation.

CONCLUSIONS: Biometric changes of the human eye as a response to IOP changes were assessed in vivo. The correlation between change in AEL and IOP found emphasizes the need of in vivoocular rigidity measurements in the human eye.

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Effects of changes in intraocular pressure on human ocular haemodynamics.

Curr. Eye Res., 1997; 1024-9

PURPOSE: Myogenic autoregulation is the ability of a vascular bed to maintain blood flow despite changes in perfusion pressure. Ocular perfusion pressure is defined as the difference between ocular arterial pressure and ocular venous pressure, the latter dependent on intraocular pressure (IOP). The aim of the present study was to investigate the effect of moderate increases in IOP on ocular haemodynamics.

METHODS: Changes in IOP (+ 10 mmHg, +20 mmHg) were induced by a suction cup in 10 healthy subjects. Ocular fundus pulsations in the macula and the optic disc were measured by laser interferometry; blood flow velocities in the central retinal artery (CRA) and in the ophthalmic artery (OA) were measured by Doppler sonography.

RESULTS: Changes in IOP caused a significant reduction in fundus pulsations, which was more pronounced in the macula (at +10 mmHg: -9 +/- 2%, p < 0.01; at +20 mmHg: -19 +/- 3%, p < 0.001) than in the optic disc (at +10 mmHg: -5 +/- 2% (ns); at +20 mmHg: -9 +/- 3%, p < 0.01). Mean flow velocity in the CRA was reduced by -5 +/- 3% at +10 mmHg (ns) and by -14 +/- 5% at +20 mmHg (p < 0.005), resistive index was increased by +4 +/- 1% at +10 mmHg (p < 0.05) and by +6 +/- 2% at +20 mmHg (p < 0.01). In contrast, a rise in IOP did not affect blood flow parameters in the OA.

CONCLUSIONS: Our results from fundus pulsation measurements indicate that choroidal blood flow decreases when IOP is increased. The Doppler sonographic findings in the CRA indicate reduced blood flow velocity in this artery during raised IOP.

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Effects of endothelin-1 (ET-1) on ocular hemodynamics.

Curr. Eye Res., 1997; 687-92

PURPOSE: There is evidence from in vitro and animal data that endothelin-1 (ET-1) plays an important role in ocular blood flow. The aim of the present study was to investigate the effect of systemic ET-1 administration on ocular circulation in healthy subjects.

METHODS: In a double blind, placebo-controlled, randomized, 2-way cross over study in 10 healthy male subjects, we administered stepwise, increasing doses of ET-1 (0 (saline), 1.25, 2.5 and 5.0 ng/kg/minutes; 20 minutes per dose (level) or placebo. Blood flow velocity in the ophthalmic artery as well as ocular fundus pulsations in the macula and the optic disc, and systemic hemodynamic parameters were measured.

RESULTS: ET-1 dose-dependently reduced fundus pulsations in the macula (maximum effect -12 +/- 2% versus baseline; p < 0.001 versus baseline and placebo) and the optic disc (maximum effect: -19 +/- 5% versus baseline; p < 0.001 versus baseline and placebo), but did not affect blood flow velocity in the ophthalmic artery or systemic hemodynamics.

CONCLUSIONS: Endothelin-1 reduces pulsatile blood flow in the choroid and the optic disc at doses which do not affect systemic hemodynamics or flow velocity in the ophthalmic artery. These results indicate that ocular circulation is particularly sensitive to changes in local ET-1 concentration and confirms the hypothesis that ET-1 may play a role in ocular vascular diseases.

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Effects of insulin on retinal and pulsatile choroidal blood flow in humans.

Arch. Ophthalmol., 2000; 55-9

BACKGROUND: Insulin induces vasodilation in several tissues, including skeletal muscle and kidneys.

OBJECTIVE: To investigate whether insulin may contribute to ocular blood flow regulation.

METHODS: The study was performed in a balanced, randomized, placebo-controlled, single-masked, 3-way, crossover design in 9 healthy male subjects. Each subject received 2 doses of insulin (1.5 or 3 mU/kg per minute) or placebo on 3 different study days. Measurements of fundus pulsation amplitude with laser interferometry to assess pulsatile choroidal blood flow, of retinal blood flow with the blue-field entoptic technique, and of mean blood flow velocity in the ophthalmic artery with Doppler sonography were performed under euglycemic clamp conditions over 120 minutes.

RESULTS: Hyperinsulinemia significantly increased fundus pulsation amplitude (1.5 mU/kg per minute: 8.7% +/- 1.1% vs baseline; 3 mU/kg per minute: 13.2% +/- 2.3% vs baseline; P<.001 vs placebo [analysis of variance]) and mean blood flow velocity (1.5 mU/kg per minute: 10.0% +/- 4.3% vs baseline; 3 mU/kg per minute: 6.6% +/- 3.5% vs baseline; P = .03 vs placebo). Retinal blood flow did not increase during administration of insulin (1.5 mU/kg per minute: 6.4% +/- 8.0% vs baseline; 3 mU/kg per minute: 8.0% +/- 5.1% vs baseline; P = .99 vs placebo). Neither the effect in the choroid nor that in the ophthalmic artery was dose-dependent.

CONCLUSION: Hyperinsulinemia significantly increases choroidal blood flow and mean blood flow velocity in the ophthalmic artery. By contrast, retinal blood flow was not influenced by hyperinsulinemia. The maximum effective dose of insulin for ocular hemodynamics is likely to be within the physiological range.

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Effects of losartan on cerebral and ocular circulation in healthy subjects.

Br J Clin Pharmacol, 1997; 369-75

AIMS: The introduction of specific inhibitors of AT1 receptors, such as losartan, has enabled the investigation of the renin-angiotensin-system (RAS) in humans in vivo. We studied the role of the RAS in the cerebral and ocular circulation in healthy subjects. Haemodynamic effects of orally administered losartan were investigated with non-invasive methods.

METHODS: In a placebo-controlled randomized, double-blind two way crossover design losartan (100 mg orally) or placebo was administered in 10 healthy subjects. The effect of losartan was studied at hourly intervals for 8 h. In addition, the effect of losartan on haemodynamic changes induced by exogenous angiotensin II (Ang II) was assessed. Blood flow velocities in the ophthalmic and the middle cerebral artery (OA, MCA) were measured with Doppler sonography. Pulsatile choroidal blood flow was estimated with laser interferometric measurement of fundus pulsation.

RESULTS: Losartan significantly increased fundus pulsation amplitude (+11%, 95% CI: 5 to 16% P<0.0001), tended to increase resistive index in the ophthalmic artery (+12%, 95% CI: 0 to 23%) and tended to decrease mean arterial pressure (-15%, 95% CI: -23 to -1%). Ang II induced effects on cerebral, ocular and systemic haemodynamics were prevented by preceding administration of losartan.

CONCLUSIONS: The present data suggest that Ang II is not a major determinant of cerebral and ocular blood flow in vivo. The observed changes in cerebral and ocular haemodynamic parameters after losartan administration reflect effects on systemic blood pressure.

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Effects of moderate changes in intraocular pressure on ocular hemodynamics in patients with primary open-angle glaucoma and healthy controls.

Ophthalmology, 2005; 1337-42

PURPOSE: There is some indirect evidence for altered autoregulation in patients with glaucoma, but only a few studies have measured ocular blood flow directly during changes in ocular perfusion pressure. The present study was designed to compare pulsatile choroidal blood flow and optic nerve head (ONH) blood flow during moderate increases in intraocular pressure (IOP) in patients with primary open-angle glaucoma (POAG) and normal controls.

DESIGN: Two nonrandomized studies comparing blood flow responses in glaucoma patients and controls in an open design.

PARTICIPANTS AND CONTROLS: Sixteen patients with POAG glaucoma and 16 healthy gender-matched and age-matched controls were included in the choroidal blood flow experiments. The ONH blood flow experiment was performed in 14 POAG patients and 14 healthy gender-matched and age-matched controls.

METHODS: In the first study, pulsatile choroidal blood flow was assessed by laser interferometric measurement of fundus pulsation amplitude (FPA). In the second study, ONH blood flow was measured using laser Doppler flowmetry. In both cohorts, the IOP was increased stepwise by 10 and 20 mmHg using a suction cup.

MAIN OUTCOME MEASURES: Fundus pulsation amplitude and ONH blood flow.

RESULTS: The baseline values of FPA and ONH blood flow were lower in glaucoma patients as compared with age-matched and gender-matched healthy controls. In patients with POAG, FPA decreased by -4.5+/-5.8% and -11.3+/-4.9% during elevation of IOP of 10 and 20 mmHg, respectively. These results were not different from the results in healthy controls, where FPA decreased by -5.1+/-3.4% and -12.2+/-4.9% at the 2 pressure levels (P = 0.23 between groups). Optic nerve head blood flow showed no changes during the increase of IOP of 10 and 20 mmHg in either of the 2 groups (glaucoma patients, +2.1+/-14.7% and -0.8+/-15.2%; healthy controls, +4.3+/-12.0% and +0.2+/-14.2%; P = 0.83 between groups).

CONCLUSIONS: The present study does not provide evidence for altered autoregulation in patients with POAG during a moderate increase in IOP. However, these results do not necessarily contradict the concept of vascular dysregulation in glaucoma.

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Effects of peribulbar anesthesia on ocular blood flow in patients undergoing cataract surgery.

Am. J. Ophthalmol., 1999; 645-9

PURPOSE: The effects of extraconal, peribulbar anesthesia on ocular blood flow may be caused by concomitant elevations in intraocular pressure or direct pharmacologic alteration of vascular tone. We quantified the effect on ocular circulation with a new technique for assessment of ocular hemodynamics.

METHODS: In a prospective study, ocular hemodynamics were measured before and 1 and 5 minutes after peribulbar anesthesia in 22 eyes with age-related cataract. Measurements included fundus pulsation amplitude with a laser interferometric method assessing the pulsatile choroidal blood flow and mean blood flow velocity as well as resistive index in the ophthalmic and central retinal artery with Doppler sonography. Systemic blood pressure and pulse were monitored throughout the period of ocular hemodynamic measurements.

RESULTS: Fundus pulsation amplitude decreased significantly after peribulbar anesthesia (after 1 minute and 5 minutes: -13% and -8%; P < .001). In the central retinal artery, mean blood flow velocity dropped (-15%; P < .001) and resistive index increased (+3%; P = .02) 1 minute after peribulbar anesthesia compared with baseline. There were no changes in ophthalmic artery hemodynamics. Intraocular pressure was elevated 1 minute after peribulbar anesthesia (+29%; P = .003) but reached baseline values after 5 minutes.

CONCLUSION: Pulsatile choroidal blood flow and retinal blood flow velocities were reduced after peribulbar anesthesia. These reductions were still present 5 minutes after peribulbar anesthesia, when intraocular pressure had returned to baseline values. This supports the theory of drug-induced vasoconstriction after peribulbar anesthesia. A loss of vision may be a risk of peribulbar anesthesia in patients who have compromised ocular blood flow before surgery.

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Efficacy and safety of capsular bending ring implantation to prevent posterior capsule opacification: three-year results of a randomized clinical trial.

J Cataract Refract Surg, 2008; 1318-28

PURPOSE: To determine whether a capsular bending ring (CBR) with a rectangular cross-section and sharp edges moves the barrier to the very equator and avoids contact between the capsulorhexis and optic to prevent posterior capsule opacification (PCO) and anterior capsule fibrosis.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: A 0.7 mm high, open poly(methyl methacrylate) CBR was implanted in 60 eyes (patients) in a prospective randomized intraindividual trial. The impact of additional CBR implantation on PCO and anterior capsule fibrosis was compared to that of intraocular lens (IOL) implantation alone using objective scoring.

RESULTS: No CBR-related surgical complications occurred. The objective PCO score and area were statistically significantly reduced in the CBR group. In patients with complete follow-up, the mean PCO score (scale 1 to 10) at 1, 2, and 3 years was 0.8, 1.7, and 2.1, respectively, in the CBR group and 2.6, 3.9, and 4.6, respectively, in the no-CBR group. The number of quadrants affected by PCO was 0.9, 1.5, and 1.8 versus 3.2, 3.8, and 3.8. Barrier failures with the CBR were caused by the inherent slight edge blunting and occasional eyelet gaping. Laser capsulotomies were performed in the no-CBR group only. Capsule stress folds and fibrotic anterior capsule opacification were also greatly reduced. The best corrected visual acuity was better in the CBR group.

CONCLUSIONS: Capsular bending ring implantation was an effective and safe adjunct to in-the-bag IOL fixation. With improvements in technology and design securing exquisitely sharp edges and circumferential capsular bending independent of the capsular bag diameter, this concept has the potential to prevent PCO and anterior capsule fibrosis.

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Efficacy and tolerability of preservative-free and preserved diclofenac and preserved ketorolac eyedrops after cataract surgery.

Am. J. Ophthalmol., 2010; 777-84

PURPOSE: To compare the anti-inflammatory efficacy and subjective tolerability of preservative-free and preserved diclofenac 0.1% and preserved ketorolac 0.5% eye drops for prophylaxis and management of inflammation after cataract surgery.

DESIGN: Prospective, randomized, investigator-masked, parallel-group, comparative clinical trial.

METHODS: One hundred two patients who underwent small-incision phacoemulsification cataract surgery in an institutional setting were assigned randomly to receive preservative-free diclofenac sodium 0.1% (Voltaren ophtha SDU; Novartis Pharma), preserved diclofenac sodium 0.1% (Voltaren ophtha; Novartis Pharma), or preserved ketorolac tromethamine 0.5% (Acular; Pharm Allergan) eyedrops 4 times daily for 4 weeks after surgery. During the 1-month follow-up, anterior chamber flare and mean foveal thickness were evaluated for objective comparison of the anti-inflammatory effect. Ocular tolerability was assessed by observer-based grading of conjunctival hyperemia and ocular discomfort, as well as obtaining subjective ratings of ocular tolerability on a visual analog scale. Distance and near visual acuity and intraocular pressure served as safety measures.

RESULTS: All 3 formulations demonstrated equal anti-inflammatory efficacy as measured by reduction of anterior chamber flare after surgery and prevention of postoperative macular edema. Patients treated with preservative-free diclofenac eyedrops reported significantly better subjective tolerability values (P = .001), were classified as having less ocular discomfort (P < .001), and experienced earlier reduction of postoperative conjunctival hyperemia (P = .029).

CONCLUSIONS: Anti-inflammatory efficacy was comparable for all 3 agents. However, preservative-free diclofenac 0.1% eyedrops exhibited a significantly better postoperative subjective and objective tolerability when compared with preserved eyedrops containing ketorolac or diclofenac.

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Efficacy of ophthalmic viscosurgical devices in maintaining corneal epithelial hydration and clarity: in vitro assessment.

J Cataract Refract Surg, 2012; 2154-9

PURPOSE: To determine the efficacy of hydroxypropyl methylcellulose (HPMC) and hyaluronic acid (HA) in maintaining corneal hydration and optical clarity.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

DESIGN: Experimental study.

METHODS: In porcine autopsy eyes, the effect of 13 ophthalmic viscosurgical devices (OVDs) (5 formulations of HPMC; 8 formulations of HA) in maintaining corneal hydration and optical clarity was tested. The main outcome variables were the time to reach optical clarity of the cornea during dissipation of the OVD and duration of corneal hydration. These variables were assessed after the first application of the OVD, after balanced salt solution application to rehydrate the gel matrix, and after the second application of OVD on top of the first layer.

RESULTS: The study used 57 porcine eyes. High-molecular-weight HA 1.5% (zero shear viscosity [ZSV] 55,122 millipascal seconds [mPa.s]) took a significantly shorter time to reach optical clarity than HA 1.4% (ZSV 36,882 mPa.s) (P=.04). Hyaluronic acid 1.4% and HA 1.5% maintained corneal hydration significantly longer than HPMC 2.0% (P<.001).

CONCLUSIONS: For corneal hydration during short-lasting surgical procedures such as cataract surgery, the results suggest using HPMC because it distributes quickly and provides an adequate duration of sufficient corneal hydration. For corneal hydration during prolonged surgical procedures, such as vitreoretinal surgery, results suggest using HA 1.5% in the formulation because it provides long-lasting corneal hydration.

FINANCIAL DISCLOSURE: Dr. Prinz has a proprietary interest in Croma Pharma GmbH, Leobendorf, Austria. Dr. Findl is a scientific advisor to Croma Pharma GmbH. No other author has a financial or proprietary interest in any material or method mentioned.

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Endothelin-1 contributes to hyperoxia-induced vasoconstriction in the human retina.

Invest. Ophthalmol. Vis. Sci., 2000; 864-9

PURPOSE: There is evidence that ocular blood flow strongly depends on arterial oxygen tension. Results from recent animal studies indicate that the vasoconstrictor response to hyperoxia may be mediated in part by an increased production of endothelin (ET)-1. In an effort to answer the question whether the retinal vasoconstrictive response to hyperoxia in humans is mediated through ET-1, changes in ocular hemodynamics induced by 100% O2 breathing were studied in the absence and presence of an ET(A) receptor antagonist (BQ-123).

METHODS: The study was a randomized, placebo-controlled, double-masked, balanced, three-way crossover design. On separate study days 15 healthy male subjects received infusions of BQ-123 (either 60 microg/min or 120 microg/min) or placebo. The effects of BQ-123 or placebo on hyperoxia-induced (100% O2 breathing) changes in retinal and pulsatile choroidal blood flow were assessed with the blue-field entoptic technique and with laser interferometric measurement of fundus pulsation, respectively.

RESULTS: During baseline conditions, hyperoxia caused a decrease in retinal blood flow between -29% and -34% (P<0.001) and a decrease in fundus pulsation amplitude between -7% and -8% (P<0.001). BQ-123 dose dependently blunted the response to hyperoxia in the retina (60 microg/min: -25%, 120 microg/min: -20%; P = 0.003), but not in the choroid.

CONCLUSIONS: These results indicate that ET-1 contributes to hyperoxia-induced retinal vasoconstriction in the human retina.

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Enhanced Penetration for Axial Length Measurement of Eyes with Dense Cataracts Using Swept Source Optical Coherence Tomography: A Consecutive Observational Study.

Ophthalmol Ther, 2018;

INTRODUCTION: The aim of this study was to find cases in which the axial eye length could not be measured with partial coherence interferometry (PCI) technology and to assess if it could be measured using swept source optical coherence tomography (ss-OCT) technology.

METHODS: All patients were measured at their pre-assessment visit 1 week prior to cataract surgery using conventional optical biometry (PCI technology, IOLMaster 500, Carl Zeiss Meditec AG, Jena, Germany). Patients in whom one or both eyes could not be measured using PCI technology were invited to participate in the study and to be measured with the ss-OCT (IOL Master 700, Carl Zeiss Meditec AG, Jena, Germany) device.

RESULTS: Altogether, 1226 eyes of 613 patients were measured consecutively, and 78 eyes were not measured successfully with PCI technology. Among those with unsuccessfully measured eyes, 23 patients were willing to participate in the study, and two of those were also unsuccessfully measured with the ss-OCT device (8.7%, 2/23). However, 91.3% (21/23) of the eyes that were unsuccessfully scanned with PCI technology were measurable with the ss-OCT device. The estimated overall rate of unsuccessful scans with the ss-OCT device was 0.5% (6/1226) ([Formula: see text] < 0.01).

CONCLUSION: ss-OCT technology significantly improves the rate of attainable axial eye length measurements, especially in eyes with posterior subcapsular cataracts, but also in eyes with dense nuclear cataracts, except for white cataracts.

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Enhanced visualization of macular pathology with the use of ultrahigh-resolution optical coherence tomography.

Arch. Ophthalmol., 2003; 695-706

OBJECTIVES: To demonstrate a new generation of ophthalmic optical coherence tomography (OCT) technology with unprecedented axial resolution for enhanced imaging of intraretinal microstructures and to investigate its clinical feasibility to visualize intraretinal morphology of macular pathology.

METHODS: A clinically viable ultrahigh-resolution ophthalmic OCT system was developed and used in clinical imaging for the first time. Fifty-six eyes of 40 selected patients with different macular diseases including macular hole, macular edema, age-related macular degeneration, central serous chorioretinopathy, epiretinal membranes, and detachment of pigment epithelium and sensory retina were included.

OUTCOME MEASURES: Ultrahigh-resolution tomograms visualizing intraretinal morphologic features in different retinal diseases.

RESULTS: An axial image resolution of approximately 3 micro m was achieved in the eyes examined, nearly 2 orders of magnitude better than conventional ophthalmic ultrasound. Ultrahigh-resolution OCT images provided additional diagnostically important information on intraretinal morphologic features that could not have been obtained by standard techniques.

CONCLUSIONS: Ultrahigh-resolution ophthalmic OCT enables unprecedented visualization of intraretinal morphologic features and therefore has the potential to contribute to a better understanding of ocular pathogenesis, as well as to enhance the sensitivity and specificity for early ophthalmic diagnosis and to monitor the efficacy of therapy. This study establishes a baseline for the interpretation of ultrahigh-resolution ophthalmic OCT imaging of macular diseases.

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Eplerenone in patients with chronic recurring central serous chorioretinopathy.

Eur J Ophthalmol, 2016; 479-84

PURPOSE: To evaluate the effect of eplerenone on patients with long-term recurring central serous chorioretinopathy (CSC).

METHODS: In this retrospective case series, 11 patients with chronic recurring CSC were included. The main focus was to include patients who had undergone photodynamic therapy (4 patients), had undergone anti-vascular endothelial growth factor treatment (3 patients), or had several episodes of CSC in the past (4 patients) (mean age 60 years; SD 9.7, range 47-76).

RESULTS: Four patients (36.4%) had full resorption of neurosensory detachment under therapy of eplerenone with improvement of vision, while 4 more patients had improvement of vision despite residual edema. Eight patients (73%) had improved visual acuity (VA) at the end of eplerenone therapy, 2 patients had no change in VA, and 1 patient decreased VA. Mean time of treatment was 10.6 ± 9.9 weeks (range 3-38 weeks). All patients showed subretinal deposits, with 6 of them having hyperautofluorescent subretinal deposits.

CONCLUSIONS: Eplerenone represents a new treatment option for patients with CSC. Our data indicate a good response in those patients, leading to improvement of VA in 73% of patients.

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European multicenter trial of the prevention of cystoid macular edema after cataract surgery in nondiabetics: ESCRS PREMED study report 1.

J Cataract Refract Surg, 2018; 429-439

PURPOSE: To compare the efficacy of a topical nonsteroidal antiinflammatory drug, topical corticosteroid, and a combination of both drugs to prevent the occurrence of cystoid macular edema (CME) after cataract surgery in nondiabetic patients.

SETTING: Twelve European study centers.

DESIGN: Randomized clinical trial.

METHODS: Nondiabetic patients having uneventful cataract surgery were included in this study. Patients were randomized to receive topical bromfenac 0.09% twice daily for 2 weeks or dexamethasone 0.1% 4 times daily with 1 drop less per day every following week, or a combination of both. The primary outcome was the difference in central subfield mean macular thickness 6 weeks postoperatively. Secondary outcome measures included corrected distance visual acuity as well as the incidence of CME and clinically significant macular edema (CSME) within 6 weeks and 12 weeks postoperatively.

RESULTS: This study comprised 914 patients. Six weeks postoperatively, the central subfield mean macular thickness was 288.3 μm, 296.0 μm, and 284.5 μm in the bromfenac group, dexamethasone group, and combination treatment group, respectively (overall P = .006). The incidence of clinically significant macular edema within 12 weeks postoperatively was 3.6%, 5.1%, and 1.5%, respectively (overall P = .043).

CONCLUSION: Patients treated with a combination of topical bromfenac 0.09% and dexamethasone 0.1% had a lower risk for developing CSME after cataract surgery than patients treated with a single drug.

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Evaluation of 2 new optical biometry devices and comparison with the current gold standard biometer.

J Cataract Refract Surg, 2011; 513-7

PURPOSE: To compare 2 new optical biometry devices with the present gold standard biometer.

SETTING: Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

DESIGN: Evaluation of diagnostic test or technology.

METHODS: In patients scheduled for cataract surgery, measurements performed with the current gold standard optical biometer (IOLMaster) were compared with those of 2 new optical biometers, the Lenstar LS 900 (optical low-coherence reflectometry [OLCR] device; substudy 1) and the IOLMaster 500 (partial coherence interferometry [PCI] device; substudy 2). The duration of patient data entry and of the actual measurement process and the time from intraocular lens power calculation to printout were calculated.

RESULTS: The mean difference in axial length measurements was 0.01 mm ± 0.05 (SD) between the gold standard device and the new OLCR device and 0.01 ± 0.02 mm between the gold standard device and the new PCI device (P=.12 and P < .001, respectively). Measurements with the new OLCR device took significantly longer than with the gold standard device (mean difference 209 ± 127 seconds), and measurements with the gold standard device took significantly longer than with the new PCI device (mean difference 82 ± 46 seconds) (both P < .001).

CONCLUSIONS: All 3 devices were easy to use for biometry before cataract surgery. Measurements with the new PCI device took half as long as those with the gold standard device. Measurements with the new OLCR device took twice as long as those with the gold standard device.

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Evaluation of 4 corneal astigmatic marking methods.

J Cataract Refract Surg, 2012; 2094-9

PURPOSE: To compare 4 devices used to mark the cornea before astigmatism-reducing surgery.

SETTING: Hanusch Krankenhaus, Vienna, Austria.

DESIGN: Randomized examiner-masked clinical trial.

METHODS: Patients were randomly allocated to 1 of 4 groups for preoperative corneal marking in the sitting position. The 4 methods used were marking at the slitlamp with an insulin needle, a pendular marker, a bubble marker, and a tonometer marker. The marks were then documented with a standardized photographic technique, and the rotational deviation and vertical misalignment were assessed.

RESULTS: The study enrolled 60 patients. The pendular-marking device showed the least rotational deviation to the reference meridian (mean 1.8 degrees). There was no statistically significant difference between slitlamp marking and pendular marking (P = .05); however, there was a significant difference between the pendular marker and the bubble marker and between the pendular marker and the tonometer marker (P = .01 and P < .01, respectively). The least vertical misalignment was observed with the slitlamp-marking device (mean 0.28 mm). There was no statistically significant difference in vertical misalignment between the 4 groups.

CONCLUSIONS: All marking devices showed a slight deviation to the horizontal reference meridian. Because small deviations of the meridian can result in a relevant reduction in the astigmatism-reducing effect with toric intraocular lenses, accurate marking of the cornea before surgery is critical due to the variable cyclotorsion caused by a change from the upright to the supine position.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

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Evaluation of an electronic reading desk to measure reading acuity in pseudophakic patients.

J Cataract Refract Surg, 2014; 1462-8

PURPOSE: To compare a new electronic reading desk (Salzburg-Advanced) with conventional measurements of reading acuity.

SETTING: Vienna Institute for Research in Ocular Surgery, Hanusch Hospital, Vienna, Austria.

DESIGN: Evaluation of diagnostic test.

METHODS: In study 1, the electronic reading desk was compared with the same version of a printed reading chart. All patients were measured twice with autorefraction (Topcon KR8800) and subjective refraction. In study 2, patients were measured once. In addition, electronic reading desk measurements were obtained under different contrast and luminance levels.

RESULTS: Study 1 evaluated 100 eyes of 50 pseudophakic patients. Differences between the electronic reading desk and the printed version were small and not significant for reading speed (131.1 words per minute [wpm]±28.7 [SD] versus 134.9±20.7 wpm), reading distance (44.7±14.4 cm versus 39.6±7.6 cm), and smallest possible read print size (1.95±0.58 mm versus 2.02±0.70 mm), respectively. Study 2 evaluated 40 eyes of 20 pseudophakic patients. Reading acuity and the smallest possible read print size decreased with lower contrast and reduced luminance, whereas reading distance and reading speed did not change significantly.

CONCLUSIONS: Measurements performed with the electronic reading desk can be used interchangeably with those performed using a printed chart. The opportunity to preset standardized luminance and contrast settings could be useful for measurements in clinical trials.

FINANCIAL DISCLOSURES: Drs. Dexl and Grabner have a proprietary interest in the Salzburg Reading Desk technology as patent assignees. No other author has a financial or proprietary interest in any material or method mentioned.

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Evaluation of factors influencing the remaining astigmatism after toric intraocular lens implantation.

J Refract Surg, 2014; 394-400

PURPOSE: To evaluate the influencing factors on remaining astigmatism after implanting a toric intraocular lens during cataract surgery.

METHODS: In this observational study, consecutive patients with cataract from three different centers who received toric intraocular lenses were included. Keratometry was performed with an optical biometry device preoperatively. The IOLMaster 500 (Carl Zeiss Meditec AG, Jena, Germany) was used in Vienna, Lenstar (Haag-Streit, Köniz, Switzerland) in Castrop-Rauxel, and IOLMaster (Carl Zeiss Meditec AG) in London. Partial least squares regression was used to detect the influence of different parameters on remaining astigmatism.

RESULTS: In total, 235 eyes of 200 patients were included. Mean corneal astigmatism measured preoperatively with the optical biometry device was -2.24 ± 0.87 diopters (D) (range: -5.75 to -1.00 D). Mean absolute and vector difference between the aimed for and the postoperatively measured astigmatism were 0.48 ± 0.37 D (range: 0.00 to 2.05 D) and 0.73 ± 0.46 D (range: 0.031 to -2.20 D), respectively (P = .576). Partial least squares regression showed a significant effect of preoperatively measured corneal astigmatism and deviation between preoperative measurements of the cornea on the postoperative (unintended) remaining astigmatism.

CONCLUSIONS: The main source of error when using toric intraocular lenses is the preoperative measurement of corneal astigmatism, especially in eyes with low astigmatism. The influence of the postoperative anterior chamber depth on the cylindrical power of toric intraocular lenses and the effect of misalignment on the reduction of the astigmatism-reducing effect can be easily calculated.

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Evaluation of laser capsule polishing for prevention of posterior capsule opacification in a human ex vivo model.

J Cataract Refract Surg, 2015; 2739-45

PURPOSE: To evaluate the efficacy of a laser photolysis (LP) system in preventing posterior capsule opacification (PCO) in a human ex vivo PCO model.

SETTING: Ars Ophthalmica Study Center, Department of Ophthalmology, General Hospital Linz, Medical Faculty of Johannes Kepler University, Linz, Austria, and the Department of Ophthalmology, Ludwig-Maximillians-University, Munich, Germany.

DESIGN: Prospective randomized controlled laboratory trial.

METHODS: Open sky extracapsular cataract extraction following implantation of a capsular tension ring (CTR) into the capsular bag was performed in 28 human donor eyes. Donor eyes received LP treatment of the capsular bag fornix and the anterior capsule for 180 or 360 degrees, whereas the contralateral eyes served as a control group. Lens epithelial cell (LEC) growth onto the posterior capsule was determined objectively during 3 months of organ culture incubation.

RESULTS: The mean interval until a complete monolayer of LECs on the posterior capsule had formed was 8.2 days ± 1.2 (SD) for control eyes and 9.4 days ± 1.1 for eyes with 180-degree LP treatment (P = .042). Eyes with 360-degree treatment showed no sign of LEC growth or migration onto the posterior capsule during the entire observation period. Transmission light microscopy revealed many residual LECs on the anterior lens capsule of untreated areas, whereas no evidence of remaining LEC in areas treated with LP was found.

CONCLUSIONS: This study demonstrates complete and sustained PCO prevention by a prototype LP system in a capsular tension ring-based human ex vivo model. Laser capsule polishing has the potential to serve as a successful surgical strategy for PCO prevention.

FINANCIAL DISCLOSURE: The authors have no proprietary or financial interest in any of the materials or equipment mentioned in this study.

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Evaluation of pulsatile choroidal blood flow in branch retinal vein occlusion.

Graefes Arch. Clin. Exp. Ophthalmol., 2002; 548-50

BACKGROUND: The present study was undertaken to compare pulsatile choroidal blood flow in patients with branch retinal vein occlusion (BRVO) with the values in normal controls.

METHODS: The study included male and female patients with manifest BRVO (n=16) and a healthy sex- and age-matched control group (n=36). Fundus pulsation amplitude (FPA) was measured in the fovea by laser interferometry to assess pulsatile choroidal blood flow.

RESULTS: The FPA in eyes with BRVO (4.4 microm) was significantly higher than in the fellow eye (3.8 microm; P<0.0005). There was also a significant difference between the affected eye of the patients and the healthy control group (3.3 microm; P<0.0009).

CONCLUSION: The increase in FPA indicates increased choroidal blood flow resulting from some local mechanisms compensating for the decrease in retinal blood flow.

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Evaluation of the efficacy and safety of a standardised intracameral combination of mydriatics and anaesthetics for cataract surgery.

Br J Ophthalmol, 2016; 976-985

BACKGROUND/AIMS: To compare the efficacy and safety of intracameral (IC) administration at the beginning of cataract surgery, of Mydrane, a standardised ophthalmic combination of tropicamide 0.02%, phenylephrine 0.31% and lidocaine 1%, to a standard topical regimen.

METHODS: In this international phase III, prospective, randomised study, the selected eye of 555 patients undergoing phacoemulsification with intraocular lens (IOL) implantation received 200 μL of Mydrane (Mydrane group) just after the first incision or a topical regimen of one drop each of tropicamide 0.5% and phenylephrine 10% repeated three times (reference group). The primary efficacy variable was achievement of capsulorhexis without additional mydriatics. The non-inferiority of Mydrane to the topical regimen was tested. The main outcome measures were pupil size, patient perception of ocular discomfort and safety.

RESULTS: Capsulorhexis without additional mydriatics was performed in 98.9% of patients and 94.7% in the Mydrane and reference groups, respectively. Both groups achieved adequate mydriasis (>7 mm) during capsulorhexis, phacoemulsification and IOL insertion. IOL insertion was classified as 'routine' in a statistically greater number of eyes in the Mydrane group compared with the reference group (p=0.047). Patients in the Mydrane group reported statistically greater comfort than the reference group before IOL insertion (p=0.034). Safety data were similar between groups.

CONCLUSIONS: Mydrane is an effective and safe alternative to standard eye drops for initiating and maintaining intraoperative mydriasis and analgesia. Patients who received IC Mydrane were significantly more comfortable before IOL insertion than the reference group. Surgeons found IOL insertion less technically challenging with IC Mydrane.

TRIAL REGISTRATION NUMBER: NCT02101359; Results.

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Evaluation of the Zeiss retinal vessel analyser.

Br J Ophthalmol, 2000; 1285-90

AIM: To investigate the reproducibility and sensitivity of the Zeiss retinal vessel analyser, a new method for the online determination of retinal vessel diameters in healthy subjects.

METHODS: Two model drugs were administered, a peripheral vasoconstrictor (the alpha receptor agonist phenylephrine) and a peripheral vasodilator (the nitric oxide donor sodium nitroprusside) in stepwise increasing doses. Nine healthy young subjects were studied in a placebo controlled double masked three way crossover design. Subjects received intravenous infusions of either placebo or stepwise increasing doses of phenylephrine (0.5, 1, or 2 microg/kg/min) or sodium nitroprusside (0.5, 1, or 2 microg/kg/min). Retinal vessel diameters were measured with the new Zeiss retinal vessel analyser. Retinal leucocyte velocity, flow, and density were measured with the blue field entoptic technique. The reproducibility of measurements was assessed with coefficients of variation and intraclass correlation coefficients.

RESULTS: Placebo and phenylephrine did not influence retinal haemodynamics, although the alpha receptor antagonist significantly increased blood pressure. Sodium nitroprusside induced a significant increase in retinal venous and arterial diameters (p<0.001 each), leucocyte density (p=0.001), and leucocyte flow (p=0.024) despite lowering blood pressure to a significant degree. For venous and arterial vessel size measurements short term coefficients of variation were 1.3% and 2.6% and intraclass correlation coefficients were 0.98 and 0.96, respectively. The sensitivity was between 3% and 5% for retinal veins and 5% and 7% for retinal arteries.

CONCLUSIONS: These data indicate that the Zeiss retinal vessel analyser is an accurate system for the assessment of retinal diameters in healthy subjects. In addition, nitric oxide appears to have a strong influence on retinal vascular tone.

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Eye elongation during accommodation in humans: differences between emmetropes and myopes.

Invest. Ophthalmol. Vis. Sci., 1998; 2140-7

PURPOSE: The pathophysiology and pathogenesis of myopia are still a matter of controversy. Exaggerated longitudinal eye growth is assumed to play an important role in the development of myopia. A significant correlation between refraction and amount of near-work has been reported. However, current knowledge of changes of axial eye length with accommodation is limited because clinical ultrasound biometry does not provide the precision and resolution required to thoroughly investigate these phenomena.

METHODS: Partial coherence interferometry (PCI), a noninvasive biometric technique, uses laser light with short coherence length in combination with interferometry to achieve precision in the micrometer to submicrometer range and resolution of 10 microm. In the present study this technique was used to investigate axial eye length changes in 11 emmetropic and 12 myopic eyes during monocular fixation at the far and near point. In 7 subjects, the contralateral eye has also been measured to investigate interocular differences in eye elongation.

RESULTS: All investigated eyes elongated during accommodation. This elongation was more pronounced in emmetropes than in myopes (P < 0.001). Mean accommodation-induced eye elongations of 12.7 microm (range, 8.6-19.2 microm) and 5.2 microm (range, 2.1-9.5 microm), corresponding to a dioptric change of approximately -0.036 D and -0.015 D, were obtained for emmetropes and myopes. No significant difference in accommodative amplitudes between groups (5.1 +/- 1.2 D [range, 3.8-7.1 D] versus 4.1 +/- 2.0 D [range, 1.0-7.1 D]; P = 0.14) was detected. No significant interocular difference in accommodation-induced eye elongation was revealed (P = 0.86). Also, a mean backward movement of the posterior lens pole of 38 microm (range, 9-107 microm) was observed in both study groups.

CONCLUSIONS: The detected eye elongation can be explained by the accommodation-induced contraction of the ciliary muscle, which results in forward and inward pulling of the choroid, thus decreasing the circumference of the sclera, and leads to an elongation of the axial eye length. Finally, it was demonstrated that PCI, in contrast to clinical ultrasound, is capable of characterizing eye length changes during accommodation in humans.

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Factors Influencing Efficacy of Peripheral Corneal Relaxing Incisions during Cataract Surgery.

J Ophthalmol, 2015; 706508

Purpose. To evaluate influencing factors on the residual astigmatism after performing peripheral corneal relaxing incisions (PCRIs) during cataract surgery. Methods. This prospective study included patients who were scheduled for cataract surgery with PCRIs. Optical biometry (IOLMaster 500, Carl Zeiss Meditec AG, Germany) was taken preoperatively, 1 week, 4 months, and 1 year postoperatively. Additionally, corneal topography (Atlas model 9000, Carl Zeiss Meditec AG, Germany), ORA (Ocular Response Analyzer, Reichert Ophthalmic Instruments, USA), and autorefraction (Autorefractometer RM 8800 Topcon) were performed postoperatively. Results. Mean age of the study population (n = 74) was 73.5 years (±9.3; range: 53 to 90) and mean corneal astigmatism preoperatively was -1.82 D (±0.59; 1.00 to 4.50). Mean corneal astigmatism was reduced to 1.14 D (±0.67; 0.11 to 3.89) 4 months postoperatively. A partial least squares regression showed that a high eccentricity of the cornea, a large deviation between keratometry and topography, and a high preoperative astigmatism resulted in a larger postoperative error concerning astigmatism. Conclusions. PCRI causes a reduction of preoperative astigmatism, though the prediction is difficult but several factors were found to be a relevant source of error.

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Fluctuations in corneal curvature limit predictability of intraocular lens power calculations.

J Cataract Refract Surg, 2013; 174-9

PURPOSE: To analyze fluctuations in corneal curvature over time.

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

DESIGN: Case series.

METHODS: A 3-piece IOL was implanted in 1 eye and a 1-piece IOL in the other eye through a 3.2 mm clear corneal temporal incision. Keratometry was performed preoperatively and at several points in time postoperatively. Differences between measurements were analyzed by power vectors. Statistical significance was assessed by monovariate, bivariate, and trivariate paired t tests. Acute angle shifts were determined as differences between meridians at 2 points in time.

RESULTS: Fifty patients were enrolled. From preoperatively to 1 year postoperatively, the changes in vector components (M, J0, J45) were, respectively, -0.02 diopter (D) ± 0.23 (SD) (P=.38), -0.07 ± 0.27 D (P=.02), and +0.04 ± 0.25 D (P=.14). Corresponding changes from 1 year to 2 years postoperatively were +0.01 ± 0.25 D (P=.73), +0.01 ± 0.23 D (P=.83), and +0.01 ± 0.16 D (P=.40). The meridian shift was -5 ± 32 degrees (P=.13) from preoperatively to postoperatively and +3 ± 22 degrees (P=.23) from 1 year to 2 years.

CONCLUSIONS: Surgically induced astigmatism was composed of slight flattening in the horizontal meridian and slight steepening in the oblique meridian but was insignificant in relation to random fluctuations, which were almost equally large between postoperative measurements 1 year apart. The fluctuations were not due to imprecision in measurement.

FINANCIAL DISCLOSURE: Dr. Norrby is a retiree from Abbott Medical Optics, Inc., and holder of a small amount of stock. Dr. Findl is scientific advisor to Abbott Medical Optics, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

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High precision biometry of pseudophakic eyes using partial coherence interferometry.

J Cataract Refract Surg, 1998; 1087-93

PURPOSE: To investigate the applicability of the scanning version of dual-beam partial coherence interferometry (PCI) for measuring the anterior segment and axial length of pseudophakic eyes in a clinical setting and to determine the achievable precision with this biometry technique.

SETTING: Department of Ophthalmology, Vienna General Hospital, and Institute of Medical Physics, University of Vienna, Austria.

METHODS: Partial coherence interferometry was performed in 39 pseudophakic eyes of 39 patients after implantation of a foldable acrylic intraocular lens (IOL).

RESULTS: Effective lens position (ELP), IOL thickness and lens-capsule distance (LCD) were determined with a precision of 2 to 3 microns; corneal thickness and axial eye length, with a precision of 0.8 and 5.0 microns, respectively. The mean ELP of the IOL was 4.093 mm +/- 0.290 (SD). In 7 eyes (18%), a positive LCD of 68 +/- 40 microns was detected with PCI. Mean corneal thickness was 526.4 +/- 31.5 microns; mean IOL thickness, 791.5 +/- 40.2 microns; and mean axial length, 23.388 +/- 0.824 mm.

CONCLUSION: The scanning version of PCI enables high precision (< or = 5 microns) and high resolution (approximately 12 microns) biometry of pseudophakic eyes that is better than conventional ultrasound by a factor of more than 20. For the first time, positive LCD, a possible risk factor for posterior capsule opacification, could be detected and quantified. Furthermore, this technique offers a high degree of comfort for the patient since it is a noncontact method with no need for local anesthesia or pupil dilation and has a reduced risk of corneal infection.

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High sensitive measurement of the human axial eye length in vivo with Fourier domain low coherence interferometry.

Opt Express, 2008; 2405-14

In this paper we present a system for intraocular distance measurement of the human eye in vivo with high sensitivity. The instrument is based on Fourier domain low coherence interferometry (FD-LCI). State-of- the-art FD-LCI systems are limited to a depth range of only a few mm, because the depth range is determined by the spectral resolution of the spectrometer. To measure larger distances (e.g. human eye length) we implemented two separate reference arms with different arm lengths into the interferometer. Each reference arm length corresponds to a different depth position within the sample (e.g. cornea and retina). Therefore two different depth sections, each with a depth range of a few mm can be imaged simultaneously. With the new system axial distances could be measured with a precision of 8 microm. We demonstrate the performance of the instrument by measuring the axial eye length of 9 patients with cataract and compare our results with those obtained using the IOL Master (Carl Zeiss Meditec Inc.).

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Human macula investigated in vivo with polarization-sensitive optical coherence tomography.

Invest. Ophthalmol. Vis. Sci., 2006; 5487-94

PURPOSE: To investigate a depolarizing layer that is visible in polarization-sensitive optical coherence tomography (PS-OCT) images of the retina. To identify this layer and characterize its depolarizing effect quantitatively.

METHODS: Ten healthy human subjects (mean age, 31 +/- 8 years) and two patients with RPE diseases participated in the study. The macular region of one eye of each subject was investigated with a phase-resolved PS-OCT system. The instrument measured backscattered intensity (standard OCT), phase retardation, and (cumulative) birefringent axis orientation, simultaneously. For a quantification of the depolarizing layer, plots of the distributions of retardation and axis orientation within and above this layer were analyzed.

RESULTS: A polarization-scrambling layer (PSL) was observed at the posterior boundary of the retina in PS-OCT images of all volunteers. It was identified in PS-OCT images by determining random retardation and axis orientation in a transverse direction. Measurements in patients with neurosensory retinal detachment, retinal pigment epithelium (RPE) detachment, and RPE atrophy suggest that the PSL is the RPE. The statistical analysis provided objective discrimination of the RPE from the other retinal structures.

CONCLUSIONS: PS-OCT represents a powerful tool for increasing image contrast in ocular tissues. The observed polarization-scrambling nature of the RPE may be used in diseased eyes to locate the RPE or remains of the RPE definitively in OCT images.

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Imaging of polarization properties of human retina in vivo with phase resolved transversal PS-OCT.

Opt Express, 2004; 5940-51

Recently, we developed a phase resolved polarization sensitive OCT system based on transversal scanning. This system was now improved and adapted for retinal imaging in vivo. We accelerated the image acquisition speed by a factor of 10 and adapted the system for light sources emitting at 820nm. The improved instrument records 1000 transversal lines per second. Two different scanning modes enable either the acquisition of high resolution B-scan images containing 1600x500 pixels in 500ms or the recording of 3D data sets by C-scan mode imaging. This allows acquiring a 3D-data set containing 1000x100x100 pixels in 10 seconds. We present polarization sensitive B-scan images and to the best of our knowledge, the first 3D-data sets of retardation and fast axis orientation of fovea and optic nerve head region in vivo. The polarizing and birefringence properties of different retinal layers: retinal pigment epithelium, Henle's fiber layer, and retinal nerve fiber layer are studied.

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Impact of bilateral cataract surgery on vision-related activity limitations.

J Cataract Refract Surg, 2013; 680-5

PURPOSE: To evaluate patients' vision-related activity limitation before and after bilateral cataract surgery using the German version of the Catquest-9SF questionnaire.

SETTING: Hanusch Hospital, Vienna, Austria, and Ophthalmic Clinic, Minden, Germany.

DESIGN: Questionnaire development.

METHODS: This prospective 2-center study included patients who were scheduled for bilateral cataract surgery and attended their preassessment appointment approximately 1 week before cataract surgery. All patients self-administered the Catquest-9SF at the preassessment session and a second time 3 months after cataract surgery. The questionnaire includes 9 items and is a revised short form of the Catquest, scored using Rasch analysis. The Catquest-9SF includes questions concerning vision-associated problems in everyday life, general satisfaction with vision, and difficulties performing activities.

RESULTS: The study comprised 210 patients, 120 in Austria and 90 in Germany. The mean age of all patients was 74.1 years (range 41 to 92 years). Patients mostly had difficulties doing handwork (42%) or recognizing uneven surfaces (30%). Sixty percent of the patients in Austria and approximately 50% in Germany were very unsatisfied with their vision preoperatively. Postoperatively, all patients recognized a subjective improvement in their vision.

CONCLUSIONS: Patients having bilateral cataract surgery achieved marked improvements in vision-related activity limitation and satisfaction with vision. A subset of patients with less vision-related activity limitation before surgery was satisfied with first-eye surgery only.

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Impact of intraocular lens haptic design and orientation on decentration and tilt.

J Cataract Refract Surg, 2011; 1768-74

PURPOSE: To assess the effect of intraocular lens (IOL) orientation (vertical versus horizontal) and haptic design (1-piece versus 3-piece) on centration and tilt using a Purkinje meter.

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

DESIGN: Randomized pilot study with intrapatient comparison.

METHODS: In part 1 of this study, patients received plate-haptic IOLs (Akreos Adapt) in both eyes that were positioned vertically in 1 eye and horizontally in the other eye. In part 2, patients received a 1-piece IOL (Acrysof SA60AT) in 1 eye and a 3-piece IOL (Acrysof MA60AC) in the contralateral eye. Decentration and tilt were measured 1 month and 3 months postoperatively with a new Purkinje meter.

RESULTS: In part 1 (n = 15), the mean decentration of plate-haptic IOLs was 0.4 mm ± 0.2 (SD) with vertical orientation and 0.4 ± 0.2 mm with horizontal orientation and the mean tilt, 1.5 ± 1.1 degrees and 2.9 ± 0.9 degrees, respectively. In part 2 (n = 15), the mean decentration was 0.4 ± 0.3 mm with 1-piece IOLs and 0.6 ± 0.8 mm with 3-piece IOLs and the mean tilt, 2.2 ± 7.2 degrees and 5.3 ± 2.4 degrees, respectively.

CONCLUSIONS: Three-piece IOLs had a greater tendency toward more decentration than 1-piece IOLs, perhaps because of slight deformation of 1 or both haptics during implantation or inaccuracies in production when the haptics are manually placed into the optic. The IOL orientation for plate-haptic IOLs appeared to have no effect on IOL position. The Purkinje meter was useful in assessing the capsule bag performance of the IOLs.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes.

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Improved prediction of intraocular lens power using partial coherence interferometry.

J Cataract Refract Surg, 2001; 861-7

PURPOSE: To evaluate the feasibility of using a new optical biometry technique, dual-beam partial coherence interferometry (PCI), to improve intraocular lens (IOL) power prediction in cataract surgery.

SETTING: Department of Ophthalmology, Vienna General Hospital, and Institute of Medical Physics, University of Vienna, Vienna, Austria.

METHODS: Preoperative axial length (AL) data obtained with PCI biometry and applanation ultrasound (US) biometry in 77 eyes of 51 patients was applied to 4 commonly used IOL power formulas. The refractive outcome and the mean absolute error (MAE) were calculated for each formula using both biometry methods. A linear multiple-regression model based on preoperative PCI biometry data was derived to predict the postoperative anterior chamber depth (ACD). The predictive power of this regression model was assessed by adding the predicted ACD to the SRK/T formula. Predicted residuals were calculated to evaluate the feasibility and stability of this modified IOL power formula.

RESULTS: Using PCI instead of US biometry significantly improved the refractive outcome with all 4 IOL power formulas. The Holladay I and SRK/T formulas yielded an MAE of 0.44 diopter (D) using PCI AL data and 0.56 D and 0.57 D, respectively, using US biometry data. The SRK/T formula combined with the PCI regression model for postoperative ACD prediction performed slightly better (MAE 0.42 D) than the conventional SRK/T formula alone. Predicted residuals revealed an MAE of 0.46 D, proving the predictive performance of the new formula.

CONCLUSIONS: Partial coherence interferometry biometry applied to several widely used IOL power formulas yielded significantly better IOL power prediction and therefore refractive outcome in cataract surgery than US biometry. Further improvement can be achieved by applying PCI to a modified SRK/T formula that predicts the postoperative ACD using PCI biometry data.

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Influence of a modified Nd:YAG laser treatment outside the visual axis on the morphology of Elschnig pearls.

Ophthalmic Res., 2012; 151-5

PURPOSE: To observe changes in posterior capsule opacification (PCO) after Nd:YAG treatment with and without opening the posterior lens capsule.

METHOD: This prospective randomized study included patients with regeneratory PCO. In substudy 1, a small low-energy Nd:YAG capsulotomy was performed (MiniYAG). In substudy 2, a low-energy Nd:YAG laser treatment without opening the lens capsule was performed (GentleYAG). Concerning analysis, in both substudies, the posterior capsule was divided into 4 quadrants and the quadrant where the Nd:YAG laser treatment was performed was randomly allocated. Change in PCO was analyzed using retroillumination images objectively (AQUA score: 0-10).

RESULTS: In total, 27 eyes of 25 patients were used for this study. In substudy 1, the mean amount of PCO (AQUA score) for the entire posterior capsule decreased significantly (p < 0.05, ANOVA) from 5.2 (SD: 1.6) before to 4.0 (SD: 1.9) immediately after the MiniYAG. In substudy 2, the mean amount of PCO (AQUA score) for the entire posterior capsule analyzed before and immediately after the GentleYAG was 5.1 (SD: 2.4) and 5.2 (SD: 2.3), respectively.

CONCLUSION: Performing a MiniYAG led to a significant PCO reduction. Gentle polishing of the posterior capsule resulted in a relevant reduction of PCO in one third of the patients.

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Influence of blue-light-filtering intraocular lenses on color perception and contrast acuity.

Ophthalmology, 2009; 39-45

PURPOSE: To compare contrast acuity at different illumination levels and color vision and the subjective impression in patients after bilateral cataract surgery with a mixed implantation of a blue-light-filtering and an ultraviolet (UV)-filtering intraocular lens (IOL).

DESIGN: Randomized, controlled, double-masked, and bilateral study with intraindividual comparison.

PARTICIPANTS: This study included 48 eyes of 24 consecutive patients with age-related cataract.

METHODS: Each patient had standardized small incision cataract surgery with IOL implantation into the capsular bag. Patients were randomly assigned to receive a blue-light-filtering Hoya AF-1 (UY) YA-60BB IOL in one eye and a UV-filtering Hoya AF-1 (UV) VA-60BB IOL (Hoya Medical Europe, Frankfurt/Main, Germany) in the contralateral eye. Contrast acuity was measured at illumination levels of 500, 5, and 0.5 lux and contrast levels of 100%, 50%, 25%, 12.5%, and 6.25%. Color vision was assessed using the Lanthony desaturated D-15 test, the Lanthony new color test (Munsell chroma 2 and 4), and an anomaloscope. Blue/yellow foveal threshold was tested applying short-wave automated perimetry. The subjective visual impression of patients was evaluated using a questionnaire.

MAIN OUTCOME MEASURES: Contrast acuity, color vision, and foveal threshold.

RESULTS: The blue-light-filtering IOLs had worse contrast acuity (P = 0.0004) and foveal threshold (P = 0.008) compared with the UV-filtering IOLs. Color vision tests and high-contrast visual acuity did not show any statistically significant differences between IOLs (P>0.05). On questioning, 3 of 24 patients noticed a difference between the implanted IOLs concerning visual impression.

CONCLUSIONS: This study shows that blue-light-filtering IOLs negatively affect contrast acuity and blue/yellow foveal threshold when compared with UV-filtering IOLs. Although the differences were small, the results suggest bilateral implantation of the same IOL type and avoidance of a mixed implantation of a blue-light-filtering IOL in one and a non-blue-light-filtering IOL in the contralateral eye in patients with high demands in color vision.

FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

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Influence of infusion volume on the ocular hemodynamic effects of peribulbar anesthesia.

J Cataract Refract Surg, 2006; 1509-12

PURPOSE: To test the hypothesis that ocular blood-flow response to peribulbar anesthesia can be reduced by using a smaller volume of anesthetic mixture.

SETTING: Departments of Ophthalmology and Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.

METHODS: Twenty patients scheduled for bilateral age-related cataract surgery were enrolled in a prospective randomized balanced observer-masked crossover study. Two study days with a 2 mL injection volume or 5 mL injection volume used for peribulbar anesthesia were scheduled. On 1 study day, patients received the 1-dose regimen and on the other study day, when the contralateral eye had surgery, patients received the other injection volume. On both study days, the anesthetic mixture consisted of an equal amount of lidocaine, bupivacaine, and hyaluronidase independently of the injection volume. Intraocular pressure (IOP), blood pressure, and pulse rate were measured noninvasively. Ocular fundus pulsation amplitude (FPA) and peak systolic and end diastolic flow velocities in the central retinal artery were measured with laser interferometry and color Doppler imaging, respectively. The results were recorded as means +/- SD.

RESULTS: Peribulbar anesthesia increased IOP and reduced FPA and flow velocities in the central retinal artery. The effects on IOP (5 mL, 35.1% +/- 16.0%; 2 mL, 14.1% +/- 14.1%; P<.001) and ocular hemodynamic parameters (FPA: 5 mL, -17.5% +/- 7.8%/2 mL, -7.3% +/- 7.2%, P<.001; peak systolic velocity: 5 mL, -19.5% +/- 10.7%/2 mL, -10.6% +/- 9.8%, P = .013; end diastolic velocity: 5 mL, -16.7% +/- 6.2%/2 mL, -8.4% +/- 7.3%, P = .005) were more pronounced with the 5 mL injection volume than with the 2 mL injection volume.

CONCLUSIONS: An injection volume of 2 mL instead of 5 mL reduced the ocular blood-flow response to peribulbar anesthesia. This procedure may be used in patients with ocular vascular disease to reduce the incidence of anesthesia-induced ischemia and loss of vision.

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Influence of intraocular lens material on regeneratory posterior capsule opacification after neodymium:YAG laser capsulotomy.

J Cataract Refract Surg, 2003; 1560-5

PURPOSE: To evaluate the influence of a neodymium:YAG (Nd:YAG) laser capsulotomy on the morphology and development of regeneratory opacification of the remaining surrounding posterior capsule.

SETTING: Department of Ophthalmology, Medical School, University of Vienna, Vienna, Austria.

METHODS: Standardized digital retroillumination photographs were taken immediately before and after Nd:YAG laser capsulotomy and at 1 week, 6 months, and 1 to 3 years in 38 eyes of consecutive patients. Changes in regeneratory posterior capsule opacification (PCO) and opacification around the capsulotomy opening were evaluated. The influence of the type of intraocular lens (IOL) material and design (acrylic, n = 8; hydrogel, n = 8; silicone open loop, n = 11; silicone plate haptic, n = 6; poly(methyl methacrylate) [PMMA], n = 5) was assessed. The state of the anterior vitreous surface was examined at the slitlamp in all eyes.

RESULTS: In 8 of 17 eyes with a silicone IOL, reduced regeneratory PCO was observed. Massive pearl formation on the margin of the Nd:YAG capsulotomy was typical with silicone IOLs (8 eyes) but also occurred with PMMA IOLs. Eyes with acrylic IOLs had no change in regeneratory PCO after the capsulotomy. Three of 8 eyes with hydrogel IOLs had complete closure of the posterior capsulotomy opening.

CONCLUSIONS: Neodymium:YAG laser capsulotomy induced changes in the development and morphology of regeneratory PCO. Silicone and PMMA IOLs led to significant pearl formation on the capsulotomy margin, often combined with a reduction of peripheral regeneratory PCO (silicone). Hydrogel IOLs led to a higher incidence of reclosure of the Nd:YAG capsulotomy opening.

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Influence of operator experience on the performance of ultrasound biometry compared to optical biometry before cataract surgery.

J Cataract Refract Surg, 2003; 1950-5

PURPOSE: To compare measurements performed with the IOLMaster (Carl Zeiss, Meditec AG) with those obtained by applanation ultrasound (US) and manual keratometry and to evaluate the effect of operator experience on US biometry.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: The axial length (696 eyes) and anterior chamber depth (ACD) (462 eyes) were measured in 377 patients with cataract using the IOLMaster and applanation US. To assess the effect of operator experience on the biometric results, the operators were divided into 2 groups: experienced and less experienced in performing US biometry. The difference in measurements between the methods and the variability of the difference were compared between the 2 groups.

RESULTS: Applanation US measured axial length and ACD shorter than the IOLMaster; the mean numerical difference was 0.13 mm and 0.19 mm, respectively (P<.01). For axial length, the absolute difference was smaller with experienced operators than with less experienced operators (0.15 mm versus 0.22 mm) (P<.01). For ACD, experienced operators obtained a smaller difference between measurement techniques (0.21 mm versus 0.29 mm; P<.05).

CONCLUSIONS: Experienced US operators had less difference and lower variability in the difference between applanation US and IOLMaster readings for axial length and ACD measurements. The noncontact optical method, which is essentially operator independent, gave significantly more reliable biometry before cataract surgery, especially in the case of less experienced operators.

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Influence of optic edge design and anterior capsule polishing on posterior capsule fibrosis.

J Cataract Refract Surg, 2004; 658-62

PURPOSE: To evaluate the role of posterior optic edge design and the effect of anterior capsule polishing on peripheral fibrotic posterior capsule opacification (PCO).

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This randomized prospective study comprised 144 eyes of 72 patients with bilateral age-related cataract. Each patient had standardized cataract surgery in both eyes by the same surgeon. Group 1 (46 patients) received a round-edged hydrophobic acrylic IOL (AMO Sensar AR40) in 1 eye and a sharp-edged hydrophobic acrylic IOL (AMO Sensar OptiEdge AR40e) in the other eye. Group 2 (26 patients) received a silicone IOL (Pharmacia CeeOn 911A) with a truncated optic in both eyes. In this group, the anterior capsule was extensively polished in 1 eye and was left unpolished in the other eye. Digital slitlamp photographs were taken 1 year postoperatively using a standardized photographic technique for fibrotic PCO. The intensity of PCO was subjectively graded (score 0 to 4) by 2 masked examiners.

RESULTS: Subjective PCO scores correlated well between the 2 examiners (r = 0.88). In Group 1, the mean PCO score was 0.26 for the OptiEdge AR40e IOL and 0.90 for the AR40 IOL (P<.01). In Group 2, the mean PCO score was 0.24 in eyes with a polished capsule and 0.17 in eyes in which the capsule was not polished (P =.31).

CONCLUSIONS: The sharp-edged OptiEdge AR40e IOL led to significantly less peripheral fibrotic PCO 1 year postoperatively than the round-edged AR40 IOL. In eyes with the sharp-edged silicone 911A IOL, anterior capsule polishing caused no significant difference in fibrotic PCO.

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Influence of optic edge design, optic material, and haptic design on capsular bend configuration.

J Cataract Refract Surg, 2005; 1888-94

PURPOSE: To assess and classify capsular bend configuration at the optic rim and its association with posterior capsule (PCO) and anterior capsule opacification (ACO) and capsulorhexis contraction with various intraocular lenses (IOLs).

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: A total of 659 post-cataract surgery eyes of 370 patients from different prospective randomized studies were evaluated. All eyes had standardized phacoemulsification surgery with implantation of an IOL in the capsular bag. The IOLs had a sharp or round optic edge design and were made of silicone, acrylic, or poly(methyl methacrylate) optic materials. One year postoperatively, the configuration of the capsular bend at the optic rim was assessed at the slitlamp, and standardized slitlamp images of ACO and fibrotic PCO were taken. One week, 1 year, and 3 years postoperatively, digital retroillumination images were taken for objective quantification of regeneratory PCO and the capsulorhexis area. The outcome measures were the type of capsular bend configuration, ACO score (0% to 100%), regeneratory PCO score (0 to 10), fibrotic PCO score (0 to 3), and amount of capsulorhexis contraction (mm(2)).

RESULTS: Four main types of capsular bend configuration were classified: parallel, "Y," right angle, and wrapping. The right-angle type was observed in the most cases (52%). Eyes with a wrapping capsular bend configuration had significantly less PCO, more capsulorhexis contraction, and more ACO than eyes with the other configurations. Wrapping capsule configuration was seen most often (55%) in round-edged silicone IOLs that had a thin optic rim.

CONCLUSION: The design and material of IOLs influenced the long-term capsular bend configuration at the optic rim. The right-angle type was the most common capsular bend configuration. Intraocular lenses with silicone optic material and a thin optic rim caused a wrapping capsule configuration and resulted in more capsulorhexis contraction and ACO, but less PCO.

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Influence of severity of nuclear cataract on optical biometry.

J Cataract Refract Surg, 2006; 1161-5

PURPOSE: To compare preoperative and postoperative measurements of the axial length (AL) performed with the IOLMaster (Carl Zeiss Meditec) to evaluate the effect of nuclear cataract on the optical biometry.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: In 245 consecutive eyes of 162 patients scheduled for cataract surgery, type and severity of cataract was evaluated using the Lens Opacities Classification System III. Preoperative and postoperative axial length measurements were performed with the IOLMaster. The postoperative readings of AL were corrected for the IOL optic material implanted.

RESULTS: The preoperative AL measurements were 0.07 mm +/- 0.05 (SD) (range -0.18 to 0.11 mm) longer than the postoperative measurements (P<.001). These differences in AL were only weakly correlated (r = -0.28, P = .01) with the nuclear cataract grade, mean 3.5 +/- 0.9.

CONCLUSION: In this study, AL measurements with optical biometry using the IOLMaster were not influenced by the severity of nuclear cataract to a clinically relevant degree. Furthermore, it was found that AL in the phakic eye was overestimated by about 0.07 mm because of a slightly too low value of the group refractive index used for the crystalline lens.

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Influence of the overall intraocular lens diameter on rotational stability.

Ophthalmic Res., 2015; 117-21

PURPOSE: To evaluate the rotational stability of two intraocular lenses (IOLs) of similar design and material but with a difference of 1 mm in overall length.

METHODS: In this prospective study patients with age-related cataract were included. An IOL with an overall diameter of 12 mm (ACR6 = small-diameter IOL) was compared to an IOL with an overall diameter of 13 mm (IDEA 613 XC = large-diameter IOL).

RESULTS: In total, 60 patients were included in this study. Absolute rotation in the small- and large-diameter groups was 4.4° (SD: 4.0; range: 0.3-17.8) and 3.0° (SD: 2.4; range: 0.1-7.8), respectively. The differences between the two IOLs were not found to be statistically significant.

CONCLUSION: The effect of the overall length of an IOL appears to have little impact on early rotation after cataract surgery.

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Internal limiting membrane flap transposition for surgical repair of macular holes in primary surgery and in persistent macular holes.

Eur J Ophthalmol, 2018; 225-228

PURPOSE: Classical or temporal internal limiting membrane (ILM) flap transposition with air or gas tamponade are current trends with the potential to improve surgical results, especially in cases with large macular holes.

METHODS: A prospective case series included patients with idiopathic macular holes or persistent macular holes after 23-G pars plana vitrectomy (PPV) and ILM peeling with gas tamponade. In all patients, 23-G PPV and ILM peeling with ILM flap transposition with gas tamponade and postoperative face-down position was performed.

RESULTS: In 7 of 9 eyes, temporal ILM flap transposition combined with pedicle ILM flap could be successfully performed and macular holes were closed in all eyes after surgery. The remaining 2 eyes were converted to pedicle ILM flap transposition with macular hole closure after surgery. Three eyes were scheduled as pedicle ILM flap transposition due to previous ILM peeling. In 2 of these eyes, the macular hole could be closed with pedicle ILM flap transposition. In 3 eyes, free ILM flap transposition was performed and in 2 of these eyes macular hole could be closed after surgery, whereas in 1 eye a second surgery, performed as pedicle ILM flap transposition, was performed and led to successful macular hole closure.

CONCLUSIONS: Use of ILM flaps in surgical repair of macular hole surgery is a new option of treatment with excellent results independent of the diameter of macular holes. For patients with persistent macular holes, pedicle ILM flap transposition or free ILM flap transposition are surgical options.

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Interventions for normal tension glaucoma.

Cochrane Database Syst Rev, 2003; CD002222

BACKGROUND: Normal tension glaucoma is a clinical condition in which the optic nerve is pathologically excavated and the visual field is disturbed. Nevertheless it has been assumed that intraocular pressure plays a role in the progression of visual field defects in this disease, but other, mainly vascular factors, have been discussed as well.

OBJECTIVES: The objective of this review is to assess the effects of medical and surgical treatments for normal tension glaucoma.

SEARCH STRATEGY: Trials were identified from the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Group trials register), MEDLINE, EMBASE and BIOSIS Previews. Bibliographies of identified trials were searched to find additional trials. In addition, investigators and pharmaceutical companies were contacted. Date of last search: January 2001.

SELECTION CRITERIA: This review includes randomised controlled trials in which medical or surgical interventions were compared to no treatment, placebo or other treatment in people with normal tension glaucoma. Two reviewers independently assessed the full text copies of the possibly relevant trials. Trial quality was assessed according to the methods set out in Section 6 of the Cochrane Reviewers' Handbook (Clarke 2000).

DATA COLLECTION AND ANALYSIS: Data were extracted by two reviewers and results were compared for differences. Discrepancies were resolved by discussion. The heterogeneity of interventions, follow-up periods and outcomes did not allow for statistical combinations of the study results.

MAIN RESULTS: According to the selection criteria on visual field loss, eight studies were included in this review. Only three studies focussed on patient relevant outcomes. In one trial a beneficial effect of lowering intraocular pressure was found, but only if data were corrected for cataract development. In two small studies a beneficial effect on visual field loss of brovincamine, a calcium antagonist was reported.

REVIEWER'S CONCLUSIONS: In one study the effect of intraocular pressure lowering on visual field outcome was only significant when data were corrected for cataract development. The results for calcium antagonists are promising, but larger trials have to be performed. Studies that focussed on reduction of intraocular pressure or haemodynamic variables are not necessarily relevant for the outcome in people with normal tension glaucoma.

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Interventions for preventing posterior capsule opacification.

Cochrane Database Syst Rev, 2010; CD003738

BACKGROUND: Posterior capsule opacification (PCO) remains the most common long-term complication after cataract surgery. It can be treated by Nd:YAG laser capsulotomy, however this may lead to other complications and laser treatment is not available in large parts of the developing world. Therefore, many studies try to find factors influencing the development of PCO.

OBJECTIVES: To summarise the effects of different interventions to inhibit PCO. These include modifications of surgical technique and intraocular lens (IOL) design, implantation of additional devices and pharmacological interventions.

SEARCH STRATEGY: We searched CENTRAL, MEDLINE, EMBASE, LILACS in March 2009 and reference lists of identified trial reports.

SELECTION CRITERIA: We included only prospective, randomised and controlled trials with a follow-up time of at least 12 months. Interventions included modifications in surgical technique explicitly to inhibit PCO, modifications in IOL design (material and geometry), implantation of additional devices and pharmacological therapy compared to each other, placebo or standard treatment.

DATA COLLECTION AND ANALYSIS: We extracted data and entered it into RevMan. We compared visual acuity data, PCO scores and YAG capsulotomy rates and performed a meta-analysis when possible.

MAIN RESULTS: Sixty six studies were included in the review. The review was divided into three parts. 1. Influence of IOL optic material on the development of PCO. There was no significant difference in PCO development between the different IOL materials (PMMA, hydrogel, hydrophobic acrylic, silicone) although hydrogel IOLs tend to have higher PCO scores and silicone IOLs lower PCO scores than the other materials. 2. Influence of IOL optic design on the development of PCO. There was a significantly lower PCO score (-8.65 (-10.72 to -6.59), scale 0 to 100) and YAG rate (0.19 (0.11 to 0.35)) in sharp edged than in round edged IOLs, however not between 1-piece and 3-piece IOLs. 3. Influence of surgical technique and drugs on the development of PCO. There was no significant difference between different types of intraoperative/postoperative anti-inflammatory treatment except for treatment with an immunotoxin (MDX-A) which led to a significantly lower PCO rate.

AUTHORS' CONCLUSIONS: Due to the highly significant difference between round and sharp edged IOL optics, IOLs with sharp (posterior) optic edges should be preferred. There is no clear difference between optic materials. The choice of postoperative anti-inflammatory treatment does not seem to influence PCO development.

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Interventions for preventing posterior capsule opacification.

Cochrane Database Syst Rev, 2007; CD003738

BACKGROUND: Posterior capsule opacification (PCO) remains the most common long-term complication after cataract surgery. It can be treated by Nd:YAG laser capsulotomy, however, this may lead to other complications and laser treatment is not available in large parts of the developing world. Therefore, many studies try to find factors influencing the development of PCO.

OBJECTIVES: To summarise the effects of different interventions to inhibit PCO. These include modifications of surgical technique and intraocular lens (IOL) design, implantation of additional devices and pharmacological interventions.

SEARCH STRATEGY: We searched CENTRAL, MEDLINE, EMBASE, LILACS in January 2007 and reference lists of identified trial reports.

SELECTION CRITERIA: We included only prospective, randomised and controlled trials with a follow-up time of at least 12 months. Interventions included modifications in surgical technique explicitly to inhibit PCO, modifications in IOL design (material and geometry), implantation of additional devices, and pharmacological therapy, compared to each other, placebo or standard treatment.

DATA COLLECTION AND ANALYSIS: Data were extracted and entered into Review Manager. Visual acuity data, PCO score and YAG capsulotomy rates were compared and a meta-analysis was performed when possible.

MAIN RESULTS: Fifty three studies were included in the review. The review was divided into three parts. (1) Influence of IOL optic material on the development of PCO. Compared to other materials, the meta-analysis of the included studies showed a significantly higher PCO score (overall effect: 12.39 (95% confidence interval: 9.82 to 14.95), scale 0 to 100) and YAG rate (odds ratio: 8.37 (3.74 to 20.36)) only in hydrogel IOLs. (2) Influence of IOL optic design on the development of PCO. There was a significantly lower PCO score (-8.65 (-10.72 to -6.59), scale 0 to 100) and YAG rate (0.19 (0.11 to 0.35)) in sharp edged than in round edged IOLs, however, not between 1-piece and 3-piece IOLs. (3) Influence of surgical technique and drugs on the development of PCO. There was no significant difference between different types of intra-/postoperative anti-inflammatory treatment except for treatment with an immunotoxin (MDX-A) leading to a significantly lower PCO rate.

AUTHORS' CONCLUSIONS: Due to the highly significant difference between round and sharp edge IOL optics, IOLs with sharp (posterior) optic edges should be preferred. There is no clear difference between optic materials, except for hydrogel IOLs, that showed more PCO than the other materials. The choice of postoperative anti-inflammatory treatment does not seem to influence PCO development.

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Intraindividual comparison of the effects of a fixed dorzolamide-timolol combination and latanoprost on intraocular pressure after small incision cataract surgery.

J Cataract Refract Surg, 2001; 706-10

To compare the effect of a fixed dorzolamide-timolol combination with that of latanoprost on intraocular pressure (IOP) after small incision cataract surgery. Department of Ophthalmology, University of Vienna, Vienna, Austria. This prospective randomized study comprised 60 eyes of 30 patients scheduled for small incision cataract surgery in both eyes. The patients were randomly assigned to receive 1 drop of a fixed dorzolamide-timolol combination or latanoprost immediately after cataract surgery in the first eye. The second eye received the other antiglaucomatous agent. Cataract surgery was performed under sodium hyaluronate 1% with a temporal 3.5 mm sutureless posterior limbal incision, phacoemulsification, and implantation of a foldable intraocular lens. The IOP was measured preoperatively as well as 6 and 20 to 24 hours and 1 week postoperatively. Six hours after surgery, the mean IOP decreased by -0.8 mm Hg +/- 3.2 (SD) (P =.184) in the dorzolamide-timolol group and increased by 3.6 mm Hg +/- 3.5 (P <.001) in the latanoprost group. Twenty to 24 hours after surgery, the mean IOP decreased by -2.8 +/- 2.4 mm Hg (P <.001) in the dorzolamide-timolol group and increased by 0.6 +/- 3.5 mm Hg (P =.353) in the latanoprost group. The differences between groups were significant at 6 hours (P <.001) and 20 to 24 hours (P <.001). The fixed dorzolamide-timolol combination was more effective than latanoprost in reducing IOP after small incision cataract surgery. Only the fixed dorzolamide-timolol combination prevented a postoperative IOP increase and occasional IOP spikes of 30 mm Hg or higher.

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Intraocular lens calculation accuracy limits in normal eyes.

J Cataract Refract Surg, 2008; 802-8

PURPOSE: To quantify the current accuracy limits, analyze the residual errors, and propose the next steps for prediction accuracy improvements.

SETTING: Eye hospitals in Germany, Denmark, and Austria.

METHOD: Numerical ray tracing using manufacturer's intraocular lens (IOL) data (vertex radii, central thickness, refractive index) was used for all calculations. Postoperative lens position was predicted by a simple scaling model based on measurements in 1 patient collective. The model was compared with 2 other approaches in 2 patient collectives at 2 hospitals (1121 eyes with 13 IOL models; 936 eyes with 2 models). Axial lengths were measured optically (IOLMaster, Zeiss). No parameter adjustments or individualization of IOL types or of surgeons/localizations were done. The prediction errors and measures of systematic bias for short or long eyes were used to quantify the outcome.

RESULTS: The mean prediction errors in the 2 collectives were +0.13 diopter (D) and -0.13 D and the mean absolute errors were 0.44 D and 0.50 D without bias for long or short eyes, but depending on the IOL position model approach. The differences in the mean prediction errors for the IOL types were below the allowed manufacturing tolerances and below human recognition thresholds.

CONCLUSIONS: The need to individualize and fudge parameters decreases with better physical models of the pseudophakic eye. Further improvements are possible by individual topography to extract corneal asphericity and measured pupil size to calculate the best focus, by improved position predictions based on individual measurements of the crystalline lens and by smaller tolerances for IOL manufacturing.

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Intraocular lens-capsular bag imaging with ultrahigh-resolution optical coherence tomography Pseudophakic human autopsy eyes.

J Cataract Refract Surg, 2005; 818-23

PURPOSE: To compare in vitro ultrahigh-resolution optical coherence tomography (UHR OCT) cross-sectional images of the pseudophakic human autopsy eye with histology to evaluate the potential of this imaging technique for enhanced visualization of the anterior segment, especially the capsular bag, intraocular lens (IOL), and posterior capsule opacification (PCO) formation after cataract surgery.

SETTING: Department of Medical Physics and Department of Ophthalmology, University of Vienna, Vienna, Austria, and Department of Oral and Maxillofacial Surgery Institute of Dentistry, University of Turku, Turku, Finland.

METHODS: Ultrahigh-resolution OCT images were acquired from 7 pseudophakic human autopsy eyes using 1.4 microm axial x 3.0 microm transverse resolution. The axial resolution with UHR OCT is 1.4 microm compared to 10.0 microm with the commercially available OCT. Plastic-embedded histologic sections were obtained in precise alignment with the OCT tomograms.

RESULTS: Ultrahigh-resolution OCT cross-sectional tomograms corresponded to the histologic sections. With the wavelength used (800 nm), the anterior and posterior capsules, area of lens epithelial cell growth and extracellular matrix proliferation, and IOL could be clearly visualized. The extent of capsular bag adhesion to the IOL could be detected, as well as the amount of PCO formation.

CONCLUSIONS: The improved resolution makes UHR OCT a powerful tool in anterior segment imaging and evaluation of the capacity of IOL materials and models to induce capsular bag adhesion. Ultrahigh-resolution OCT may also help in determining the area of origin of PCO after cataract surgery.

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Intraocular lens movement caused by ciliary muscle contraction.

J Cataract Refract Surg, 2003; 669-76

PURPOSE: To investigate intraocular lens (IOL) movement, measured as a change in anterior chamber depth (ACD) caused by pilocarpine-induced ciliary muscle contraction.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: In this prospective study, the ACD was measured using high-precision, high-resolution, dual-beam partial coherence interferometry in 62 pseudophakic eyes of 55 patients under pilocarpine- and cyclopentolate-induced ciliary muscle contraction and relaxation. The following were studied: 2 models of a ring-haptic IOL (designed to accommodate), a plate-haptic IOL, and 3 types of 3-piece IOLs. Measurements were performed 3 months after surgery.

RESULTS: The ring-haptic IOLs and plate-haptic IOL showed a forward movement (ring haptic 43A, -116 microm; ring haptic 43E, -222 microm; plate haptic -162 microm). The 3-piece IOLs showed no change in ACD except in 1 IOL type in which there was backward movement (156 microm).

CONCLUSIONS: Pilocarpine-induced ciliary muscle contraction caused forward movement of ring- and plate-haptic IOLs that resulted in an estimated accommodative amplitude of less than 0.50 diopter in most cases. The accommodating ring-haptic IOLs did not perform better than the conventional plate-haptic IOL.

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Intraocular lenses for restoring accommodation: hope and reality.

J Refract Surg, ; 321-3

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Intraocular pressure after small incision cataract surgery with Healon5 and Viscoat.

J Cataract Refract Surg, 2000; 271-6

PURPOSE: To evaluate the effect of Healon5 (sodium hyaluronate) and Viscoat (sodium chondroitin sulfate-sodium hyaluronate) on intraocular pressure (IOP) after bilateral small incision cataract surgery.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This prospective randomized study comprised 70 eyes of 35 consecutive patients with age-related cataract in both eyes scheduled for bilateral small incision cataract surgery. The patients were randomly assigned to receive Healon5 or Viscoat during cataract surgery in the first eye. The second eye received the other viscoelastic substance. Cataract surgery was performed in an identical fashion in both eyes, with a temporal 3.5 mm sutureless posterior limbal incision, phacoemulsification, and implantation of a foldable silicone intraocular lens. The IOP was measured preoperatively and 6 hours, 20 to 24 hours, and 1 week postoperatively.

RESULTS: At 6 hours after surgery, the mean IOP increased by 5.2 mm Hg +/- 5.3 (SD) in the Healon5 group (P < .0001) and by 10.1 +/- 8.7 mm Hg in the Viscoat group (P < .0001). The increase was significantly higher in the Viscoat group than in the Healon5 group (P = .0016). Intraocular pressure spikes of 30 mm Hg or more occurred in 2 eyes in the Healon5 group and in 10 eyes in the Viscoat group (P = .0112). Twenty to 24 hours and 1 week postoperatively, the mean IOP in the 2 groups was not statistically different.

CONCLUSIONS: Viscoat caused a significantly higher IOP increase and significantly more IOP spikes than Healon5 in the early period after small incision cataract surgery.

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Intraocular pressure rise after small incision cataract surgery: a randomised intraindividual comparison of two dispersive viscoelastic agents.

Br J Ophthalmol, 2001; 139-42

AIM: To evaluate the effects of the dispersive viscoelastic agents Ocucoat (hydroxypropyl methylcellulose 2%) and Viscoat (sodium chondroitin sulphate 4%-sodium hyaluronate 3%) on postoperative intraocular pressure (IOP) after bilateral small incision cataract surgery.

METHODS: This prospective, randomised study comprised 80 eyes of 40 consecutive patients with age related cataract in both eyes scheduled for bilateral small incision cataract surgery. The patients were randomly assigned to receive Ocucoat or Viscoat during cataract surgery of the first eye. The second eye was operated later and received the other viscoelastic agent. Cataract surgery was performed with a temporal 3.2 mm sutureless posterior limbal incision, phacoemulsification, and implantation of a foldable silicone intraocular lens. The IOP was measured preoperatively as well as 6 hours, 20-24 hours, and 1 week postoperatively.

RESULTS: At 6 hours after surgery the mean IOP increased by 4.6 (SD 5.1) mm Hg in the Ocucoat group (p<0.001) and by 8.6 (8.1) mm Hg in the Viscoat group (p<0.001). The increase was significantly higher in the Viscoat group than in the Ocucoat group (p=0.004). Intraocular pressure spikes of 30 mm Hg or more occurred in two eyes in the Ocucoat and in nine eyes in the Viscoat group (p=0.023); 20-24 hours and 1 week postoperatively the mean IOP was not statistically different.

CONCLUSION: These findings indicate that Viscoat causes a significantly higher IOP increase and significantly more IOP spikes than Ocucoat in the early period after small incision cataract surgery.

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Intraoperative Applications of OCT in Ophthalmic Surgery.

Biomed Tech (Berl), 2012;

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Investigation of dispersion effects in ocular media by multiple wavelength partial coherence interferometry.

Exp. Eye Res., 1998; 25-33

We report on quantitative measurements of group refractive indices and group dispersion in water and in human ocular media such as the cornea, the aqueous humor, the lens, artificial intraocular lenses, as well as a total value averaged over the media along the axial eye length of normal subjects and pseudophakic patients in vivo using dual beam partial coherence interferometry. Different optical thickness values due to the dispersion of the cornea are demonstrated using two spectrally displaced light sources. The displacement can be used to indirectly calculate the group dispersion of the human cornea in the spectral region between 810 nm and 860 nm. If the object under investigation is dispersive, resolution is limited due to a broadening of the detected signals. This broadening increases with group dispersion, i.e., the extent to which the group refractive index of the medium varies with wavelength and thickness of the tissue under investigation as well as with the spectral bandwidth of the light source. Measurements of the group dispersion in the cornea, lens and vitreous of pseudophakic and normal human eyes, show that the cornea and the lens are more dispersive than water-by a factor of about 5 and 2, respectively-in the investigated spectral region. The cornea is approximately threefold more dispersive than the human crystalline lens, the aqueous humor is less dispersive than water and the group dispersion of all ocular components together, averaged over the axial length of normal and pseudophakic eyes, was only slightly higher compared to that of water. Since the highly dispersive cornea and lens together have only a thickness of about one sixth of that of the axial eye length, it seems that their contribution to the group dispersive effect along the whole axial eye length is only small.

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Key Developments for Partial Coherence Biometry and Optical Coherence Tomography in the Human Eye Made in Vienna.

Invest. Ophthalmol. Vis. Sci., 2016; OCT460-74

PURPOSE: To describe key developments of optical biometry and optical coherence tomography (OCT) for ophthalmic applications made by one of the pioneering research groups.

METHODS: Partial coherence interferometry (PCI) as the basic ranging technology for modern optical biometry and for OCT was introduced for biomedical applications in the 1980s. Later, Fourier domain (FD) OCT was introduced and demonstrated to provide superior sensitivity as compared to time domain OCT. Further developments comprised ultrahigh-resolution OCT and deep-penetration OCT at wavelengths of approximately 1050 nm. Important functional extensions comprise Doppler OCT/OCT angiography, polarization-sensitive OCT, and adaptive optics OCT.

RESULTS: High-precision PCI biometry has found extensive applications in cataract surgery and in research on intraocular lens design. Optical coherence tomography, especially in the second-generation variant of FD OCT, is now indispensable for ocular diagnostics in general and for retinal diagnostics in particular; 1050 nm OCT shows improved penetration into deeper layers like the choroid.

CONCLUSIONS: The contributions of the Vienna research group helped to establish PCI biometry and FD OCT as the gold standards in their respective fields.

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Laserinterferometric assessment of pilocarpine-induced movement of an accommodating intraocular lens: a randomized trial.

Ophthalmology, 2004; 1515-21

PURPOSE: To measure the axial movement of an accommodating intraocular lens (IOL) induced by ciliary muscle contraction after application of pilocarpine.

DESIGN: Randomized, controlled, patient- and examiner-masked trial with intrapatient comparison.

PARTICIPANTS AND CONTROLS: One hundred ten eyes of 55 patients with age-related bilateral cataract.

METHODS: This study was divided into 3 parts. In the first, the accommodating IOL (1CU) was compared with a 3-piece open-loop acrylic IOL that served as the control. In the second, to assess the effect of capsule fibrosis on the potential accommodating performance of the accommodating IOL, extensive polishing of the anterior capsule with a slit cannula was compared with standard surgery. In the third, the effect of a posterior capsulorhexis was compared with that of standard surgery. Anterior chamber depth (ACD) was assessed with partial coherence interferometry, measured before and after topical application of pilocarpine 2%, and near visual acuity (VA) was evaluated 3 months after surgery.

MAIN OUTCOME MEASURE: Pilocarpine-induced change in ACD.

RESULTS: The accommodating IOL showed a forward movement under pilocarpine with a median amplitude of movement of -314 microm (95% confidence interval [CI]: -148 to -592), compared with the backward movement of 63 microm (95% CI: 161 to -41) for the open-loop control IOL (P = 0.001). Capsule polishing and a posterior capsulorhexis had no effect on IOL movement with the accommodating IOL. The median near VA with distance correction was 20/60.

CONCLUSION: Pilocarpine induced a small but significant forward movement of the accommodating IOL. However, the amount of movement was calculated to result in a refractive change of <0.5 diopters (D) in most patients, reaching 1 D or slightly more in only single cases, with a large variability of movement. Neither polishing of the capsule bag nor a posterior capsulorhexis could enhance the accommodative ability.

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Late dislocation of a hydrophilic intraocular lens: risk ratios for predisposing factors and incidence rates.

Acta Ophthalmol, 2018;

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Lens refilling to restore accommodation.

J Cataract Refract Surg, 2009; 374-82

The ultimate goal of cataract surgery, besides the restoration of distance visual acuity, is the restoration of accommodation. Lens refilling with an injectable polymer has the potential of restoring accommodation following cataract surgery. Two main difficulties have hampered the success of lens refilling strategies in the past. First was leakage of the injectable material from the capsular bag and second was after-cataract formation resulting in loss of elasticity and opacification of the lens-bag complex. Recently, simplified and highly reproducible lens refilling procedures have been introduced with a potential for clinical application to restore accommodation. We present a summary of the existing methods of lens refilling for restoration of accommodation and some obstacles to clinical application that remain.

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Linear relationship of refractive and biometric lenticular changes during accommodation in emmetropic and myopic eyes.

Br J Ophthalmol, 2007; 360-5

AIM: Aim of this study was to investigate the relationship between refractive changes in the eye and biometric changes of the human crystalline lens during accommodation. Furthermore, differences in these relationships between young, healthy emmetropic and myopic subjects were analyzed.

METHODS: Mean relative change in anterior chamber depth (ACD), lens thickness (LT), anterior segment length (ASL = ACD + LT) and in objective refraction were simultaneously assessed during near-point-induced accommodation in 10 emmetropic and 10 myopic subjects. Via a beam splitter, measurements were performed simultaneously using partial coherence interferometry (PCI) and infrared (IR) photorefraction.

RESULTS: On average, for each diopter of accommodation LT increased by 0.063 mm in emmetropic and by 0.072 mm in myopic eyes, and ACD decreased by 0.047 mm and 0.057 mm, respectively. Mean ASL, indicating the position of the posterior lens pole, increased by 0.009 mm in emmetropic and by 0.013 mm in myopic eyes. The correlation between refractive and biometric changes was found to be essentially linear in both subgroups. Differences in ACD between emmetropic and myopic eyes were statistically significant at an accommodative stimulus of -1 D (p<0.04) and -2 D (p<0.02).

CONCLUSION: The biometric and refractive changes of the human lens are highly correlated and linear in function in both emmetropic and myopic eyes.

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Local corneal thickness changes after small-incision cataract surgery.

J Cataract Refract Surg, 2006; 1667-71

PURPOSE: To assess whether a temporal limbal-corneal incision approach for phacoemulsification cataract surgery induces a gradient in corneal thickening along the horizontal meridian.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: Corneal thickness in 21 eyes of 21 patients was measured preoperatively as well as 1 day, 1 week, and 1 and 3 months after phacoemulsification through a temporal limbal-corneal incision. Measurements were performed using partial coherence interferometry (PCI) with a commercial instrument, the ACMaster (Carl Zeiss Meditec, Jena). Measurements were taken along the horizontal meridian centrally along the visual axis at 1.5 mm, 3.0 mm, and 4.5 mm eccentricity.

RESULTS: Preoperatively, there were slight nasal-temporal differences in corneal thickness at all eccentricities. The mean thickness was 522 microm +/- 34 (SD) at 1.5 mm nasally and 513 +/- 36 microm at 1.5 mm temporally (P<.01). On day 1, there was a significant mean increase in corneal thickness (38 +/- 43 microm) along all locations. The thickening was slightly more pronounced in the periphery than in the center, a difference not reaching statistical significance. At 1 week, corneal thickness returned almost to baseline at all locations except for 3.0 mm temporally, where it was slightly, but not significantly, thicker (mean 8 +/- 14 mum). At 1 month, corneal thickness at the 3.0 mm temporal location returned to baseline.

CONCLUSIONS: A nasal-temporal difference in corneal thickness was found preoperatively in all patients. Phacoemulsification through a temporal limbal-corneal incision caused an increase in corneal thickness along the horizontal meridian 1 day after surgery. The prolonged corneal thickening at 3.0 mm eccentricity temporally could be a result of the proximity to the incision site.

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Long-term changes in the morphology of posterior capsule opacification.

J Cataract Refract Surg, 2005; 2120-8

PURPOSE: To classify the morphologic appearance of posterior capsule opacification (PCO) and to observe and document the changes over longer periods of time.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: Eighty-one pseudophakic eyes of 53 patients with PCO of varying degrees were included in this prospective study. Digital retroillumination images of the posterior capsule were taken in a standardized fashion 1, 2, and 3 years after cataract surgery. The PCO morphology was classified, and changes among the 3 follow-up images were analyzed.

RESULTS: At 1, 2, and 3 years, pearls occurred in 16 (20%), 41 (51%), and 57 (63%) eyes. Pearls increased in size and number. Cases with thin layers of PCO decreased from 53 to 33 to 16 eyes. Conversely, cases with thick layers increased from 18 to 45 and 64 eyes. "Cheese holes" appeared most frequently as the predominant structure (range 47% to 51%), followed by plates (range 28% to 31%), islands (range 15% to 20%), and traces of PCO (range 1% to 5%). Changes in expansion of the PCO area were observed in 61 eyes (75%) during period 1 (1 to 2 years) and period 2 (2 to 3 years). Regions of expansion and regression in the same eye occurred in periods 1 and 2 in 11 eyes (14%) and 9 eyes (11%), respectively. The phenomenon of thinning bridges, a regression of syncytial extensions of PCO, occurred in 22 eyes (27%) and 32 eyes (40%), respectively. An overlapping growth of 2 layers was observed in 18 eyes (22%).

CONCLUSIONS: The morphology of PCO is multifaceted. Apart from the Elschnig pearls, categories such as cheese holes, plates, islands, and traces of PCO were distinguished. Over the years, pearls increased in frequency, size, and number. Expansion and regression occurred simultaneously in some cases. Two or more layers grew on top of each other in some eyes.

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Long-term course of surgically induced astigmatism after a 5.0 mm sclerocorneal valve incision.

J Cataract Refract Surg, 1998; 1642-6

PURPOSE: To study surgically induced astigmatism (SIA) after a sutureless 5.0 mm sclerocorneal valve incision.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This study evaluated SIA in 34 cases of sutureless cataract surgery with a 5.0 mm superior sclerocorneal valve incision and implantation of a poly(methyl methacrylate) intraocular lens. Keratometry was measured with a Zeiss keratometer in all cases preoperatively, and 1 day, 1 week, 1 and 3 months, and 1 and 5 years postoperatively.

RESULTS: Surgically induced astigmatism, calculated by Cravy's vector analysis, showed an initial mean with-the-rule shift of 0.35 diopter (D), followed by an against-the-rule shift to a mean of -0.30 D after 1 month. One year postoperatively, mean SIA was -0.46 D. Between 1 and 5 years postoperatively, there was a statistically significant increase in mean SIA calculated by Cravy's vector analysis; SIA increased from -0.46 D after 1 year to -0.76 D after 5 years postoperatively.

CONCLUSIONS: A small, although statistically significant, amount of postoperatively induced astigmatism occurred 5 years after a sutureless 5.0 mm sclerocorneal valve incision.

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Long-term effect of 1-piece and 3-piece hydrophobic acrylic intraocular lens on posterior capsule opacification: a randomized trial.

Ophthalmology, 2007; 1663-9

PURPOSE: To compare the intensity of posterior capsule opacification (PCO) between the 1-piece and 3-piece haptic designs of the foldable hydrophobic acrylic AcrySof intraocular lens (IOL) over a 5-year period.

DESIGN: Randomized, prospective, patient- and examiner-masked clinical trial with intraindividual comparison.

PARTICIPANTS: Fifty-two patients with bilateral age-related cataract (104 eyes).

METHODS: Each study patient had cataract surgery in both eyes and received a 1-piece AcrySof IOL in 1 eye and a 3-piece AcrySof IOL in the other eye. Follow-up examinations were performed at 1 week, 1 month, 6 months, and 1, 2, and 5 years. Digital retroillumination images were obtained of each eye. The amount of posterior capsule opacification (score range, 0-10) was assessed subjectively at the slit lamp and objectively using automated image analysis software 1, 2, and 5 years after surgery.

MAIN OUTCOME MEASURE: Posterior capsule opacification score (scale, 0-10).

RESULTS: There was no significant difference between the 1-piece and 3-piece AcrySof IOL in best-corrected visual acuity, overlap of rhexis and IOL, capsular folds, anterior capsule opacification, and posterior capsule opacification (1-piece AcrySof PCO score, 1.7+/-1.7; 3-piece AcrySof PCO score, 1.3+/-1.4; P = 0.30).

CONCLUSIONS: Modification of the IOL haptic design of the sharp optic edged AcrySof IOL from a 3-piece to a 1-piece haptic design caused no significant change in PCO intensity and neodymium:yttrium-aluminium-garnet laser treatment rate 5 years after surgery.

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Long-term effect of optic edge design in a silicone intraocular lens on posterior capsule opacification.

Am. J. Ophthalmol., 2007; 913-919

PURPOSE: To compare the posterior capsule opacification (PCO) inhibiting effect of the round anterior and sharp posterior optic edge profile of the Clariflex silicone intraocular lens (IOL) [AMO Inc, Santa Ana, California, USA] with that of the double-round edge profile of the SI40 (Phacoflex; AMO Inc, Santa Ana, California, USA) silicone IOL over a period of three years.

DESIGN: Prospective, randomized, double-masked, bilateral clinical trial.

METHODS: The study took place at the Department of Ophthalmology, Medical University of Vienna, Austria. Fifty-two patients with age-related cataracts (104 eyes) were included in the study. Each patient received an SI40 IOL (round edges) in one eye and a Clariflex IOL with OptiEdge (sharp posterior optic edge) in the other eye. Follow-up examinations were at one week, one month, six months, and one, two, and three years. Digital retroillumination images were taken of each eye. The amount of PCO was subjectively assessed with the slit-lamp and objectively assessed by automated image analysis software (the computer program Automated Quantification of After-Cataract [AQUA]; Vienna, Austria) one, two, and three years after surgery.

RESULTS: The Clariflex lens showed markedly less PCO at one, two, and three years after surgery. The mean AQUA PCO score was 1.39 for the SI40 and 0.56 for the Clariflex lens after one year, estimated at 1.64 and 0.57 after two years, and at 2.04 and 0.64, respectively, after three years (scale zero to 10; P < .001). The Nd:YAG laser capsulotomy rate was far higher in the SI40 group (Five cases vs one case at three years).

CONCLUSIONS: The sharp posterior optic edge profile of the Clariflex silicone IOL led to marked and consistently less PCO than the round-edged SI40 IOL one, two, and three years after surgery.

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Long-term effect of optic edge design in an acrylic intraocular lens on posterior capsule opacification.

J Cataract Refract Surg, 2005; 954-61

PURPOSE: To compare the posterior capsule opacification (PCO) inhibiting effect of the sharp posterior optic edge design of the Sensar OptiEdge AR40e intraocular lens (IOL) with that of the double-round edge design of the Sensar AR40 IOL over a period of 3 years.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: Fifty-three patients with bilateral age-related cataract (106 eyes) were included in this randomized prospective bilateral patient- and examiner-masked clinical trial with intraindividual comparison. Each study patient had cataract surgery in both eyes and received a Sensar AR40 IOL (anterior and posterior round optic edges) in 1 eye and a Sensar OptiEdge AR40e IOL (round anterior and sharp posterior optic edge) in the other eye. Follow-up examinations were at 1 week, 1 and 6 months, and 1, 2, and 3 years. Digital retroillumination images were taken of each eye. The amount of PCO was assessed subjectively at the slitlamp and objectively using automated image-analysis software (AQUA) 1, 2, and 3 years after surgery.

RESULTS: The sharp-edged AR40e lens showed significantly less regeneratory and fibrotic PCO 1, 2, and 3 years after surgery. The mean AQUA PCO score was 2.18 for the AR40 and 1.00 for the AR40e lens after 1 year; 2.94 and 1.56 after 2 years, and estimated at 3.13 and 1.77, respectively, after 3 years (scale 0 to 10; P<.001). The neodymium:YAG laser capsulotomy rate was significantly higher in the AR40 group. The AR40e lens also led to less peripheral fibrotic PCO. There was no significant difference in complaints concerning edge glare between the groups.

CONCLUSION: Compared with the AR40 IOL, the sharp posterior optic edge design of the Sensar OptiEdge AR40e IOL led to significantly less PCO 1, 2, and 3 years postoperatively. In contrast with most past studies on PCO-preventative factors, this study varied only 1 parameter, namely the optic edge design, and the main outcome measure (PCO) was assessed with an objective image-analysis system.

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Long-term effect of sharp optic edges of a polymethyl methacrylate intraocular lens on posterior capsule opacification: a randomized trial.

Ophthalmology, 2005; 2004-8

PURPOSE: To compare the posterior capsule opacification (PCO) inhibiting effect of a 3-piece polymethyl methacrylate (PMMA) intraocular lens (IOL) with a sharp optic edge design with that of the round-edged version of the same IOL during a 5-year period.

DESIGN: Randomized patient- and examiner-masked clinical trial with intraindividual comparison.

PARTICIPANTS: Thirty-two patients with bilateral age-related cataract (64 eyes).

METHODS: Each study patient had phacoemulsification cataract surgery in both eyes and received a sharp optic edge PMMA IOL in one eye and a round optic edge PMMA IOL in the fellow eye (both by Dr Schmidt in Germany). Follow-up examinations were at 1 week, 1 month, 1 year, 3 years, and 5 years. Digital retroillumination images were taken from each eye. The amount of posterior capsule opacification was assessed objectively by means of automated image analysis software (Automated Quantification of After-Cataract) at 1 year, 3 years, and 5 years after surgery.

MAIN OUTCOME MEASURE: Posterior capsule opacification score: 0-10.

RESULTS: The sharp optic edge IOL showed significantly less regeneratory and fibrotic PCO at 1 year, 3 years, and 5 years after surgery. The mean AQUA PCO score was 5.12 for the round-edge and 2.49 for the sharp-edge IOL (scale, 0-10; P<0.001) at 5 years. The mean difference among patients for the PCO score in the eye implanted with the sharp optic edge versus the score in the eye with the round optic edge was 2.83 at 5 years (95% confidence interval, 1.66-4.00). Due to the large number of neodymium:yttrium-aluminum-garnet laser capsulotomies that were performed (12 in the round-edge group and 4 in the sharp-edge group), there was no significant difference in visual acuity between both groups at any time point.

CONCLUSIONS: Compared with the round-edge version, the sharp optic edge design of a 3-piece PMMA IOL led to significantly less PCO at 1 year, 3 years, and 5 years after surgery. However, the sharp optic edge did not lead to complete PCO prevention during this follow-up period. This finding has implications for the design of PMMA IOLs used for cataract surgery, especially in the developing world.

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Long-term efficacy of adding a sharp posterior optic edge to a three-piece silicone intraocular lens on capsule opacification: five-year results of a randomized study.

Am. J. Ophthalmol., 2005; 696-703

PURPOSE: To compare the intensity of capsule opacification with the sharp and the round optic edge variant of an open-loop hydrophobic silicone intraocular lens (IOL).

DESIGN: Randomized, controlled, double-blind clinical trial with intraindividual comparison.

METHODS: Fifty-one patients with bilateral age-related cataract were included (102 eyes). Each patient had had cataract surgery in both eyes and received a Microsil IOL with a sharp optic edge design (model S) in one eye and a Microsil IOL with a round optic edge design (model R) in the fellow eye. Both IOLs had an identical haptic design (nonangulated polymethylmethacrylate) and silicone optic material. The patients were examined at the slit lamp, best-corrected visual acuity was assessed, and standardized high-resolution digital retroillumination images of the posterior capsule were taken 5 years after surgery. The intensity of regeneratory posterior capsule opacification (rPCO), fibrotic PCO (fPCO), and anterior capsule opacification (ACO) was assessed subjectively at the slit lamp, and of rPCO, objectively using automated image analysis software (AQUA). The need for an Nd:YAG laser capsulotomy (Nd:YAG-LCT) was noted.

RESULTS: The mean AQUA PCO score was 1.2 for the model S and 2.4 for the model R lens (P = .001). The model S lens also led to less peripheral fPCO (P = .003). Concerning ACO, there was no significant difference between both IOL groups (P = .72). Whereas no capsulotomy was required with the model S, four cases (16%) had been performed in the model R group.

CONCLUSION: Five years postoperatively, the sharp-edged silicone IOL showed less rPCO and fPCO than the round-edged IOL. However, regarding ACO, there was no significant difference between both IOL styles.

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Macular disease detection with a swept-source optical coherence tomography-based biometry device in patients scheduled for cataract surgery.

J Cataract Refract Surg, 2016; 530-6

PURPOSE: To assess the sensitivity and specificity for detecting macular disease with a new optical biometry device with swept-source optical coherence tomography (SS-OCT) used before cataract surgery.

SETTING: Hanusch Hospital, Vienna, Austria.

DESIGN: Consecutive case series.

METHODS: This study included patients with or without macular disease. All patients were scanned using the new biometry device (IOLMaster 700), which allows a 1.0 mm central retinal scan using SS-OCT technology. Also, all eyes were assessed using a dedicated retinal OCT device (RTVue) on the same day. Two experienced examiners and 1 ophthalmology resident graded all scans individually. Sensitivity and specificity for detecting macular disease were assessed, as were the receiver operating characteristic curves.

RESULTS: Of the 125 eyes included, 5 were excluded from the analysis, 65 had a macular disease, and 55 were healthy. The sensitivity of the biometry device was moderate (between 42% and 68%), and the specificity was high (89% to 98%). Intraobserver reproducibility for assessing the biometry device was 88.3%.

CONCLUSIONS: The biometry device with SS-OCT provided useful information concerning the macula, especially for intraretinal fluid and macular holes. However, it cannot replace a macular OCT device.

FINANCIAL DISCLOSURE: None of the authors has a financial or proprietary interest in any material or method mentioned.

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Medical interventions for primary open angle glaucoma and ocular hypertension.

Cochrane Database Syst Rev, 2007; CD003167

BACKGROUND: Primary open angle glaucoma (POAG) is a progressive optic neuropathy with an elevated intraocular pressure (IOP), where the optic nerve head becomes pathologically excavated and the visual field (VF) is characteristically altered. Ocular hypertension (OHT) is a condition with elevated IOP but without discernible pathology of the optic nerve head or the VF. It is a major risk factor for development of POAG.

OBJECTIVES: To assess and compare the effectiveness of topical pharmacological treatment for POAG or OHT to prevent progression or onset of glaucomatous optic neuropathy.

SEARCH STRATEGY: We searched CENTRAL, MEDLINE and EMBASE in May 2007. We searched the bibliographies of identified articles and contacted experts, investigators and pharmaceutical companies for additional published and unpublished studies.

SELECTION CRITERIA: Randomised controlled trials comparing topical pharmacological treatment to placebo, no treatment or other treatment for specified endpoints which included people with POAG or OHT, and with duration of treatment of at least one year.

DATA COLLECTION AND ANALYSIS: Two authors independently extracted data and assessed trial quality. Where appropriate, we summarised data using Peto odds ratio and mean difference after testing for heterogeneity between studies.

MAIN RESULTS: We included 26 trials, which randomised 4979 participants, in this review. Meta-analysis of 10 trials clearly demonstrated reduction of onset of VF defects in treated OHT (OR 0.62, 95% CI 0.47 to 0.81). No single drug showed a significant VF protection compared to placebo or untreated controls. We did identify some border line evidence for a positive influence of treatment on VF prognosis (OR 0.67, 95% CI 0.45 to 1.00) for the beta-blockers .

AUTHORS' CONCLUSIONS: The results of this review support the current practice of IOP lowering treatment of OHT. A visual field protective effect has been clearly demonstrated for medical IOP lowering treatment. Positive but weak evidence for a beneficial effect of the class of beta-blockers has been shown. Direct comparisons of prostaglandins or brimonidine to placebo are not available and the comparison of dorzolamide to placebo failed to demonstrate a protective effect. However, absence of data or failure to prove effectiveness should not be interpreted as proof of absence of any effect. The decision to treat a patient or not, as well as the decision regarding the drug with which to start treatment, should remain individualised, taking in to account the amount of damage, the level of IOP, age and other patient characteristics.

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Meta-analysis of accommodating intraocular lenses.

J Cataract Refract Surg, 2007; 522-7

Accommodating intraocular lenses (IOLs) based on the concept of optic shift were introduced to restore accommodation after cataract surgery. Currently, 3 types of accommodating IOLs are commercially available: 1CU (HumanOptics), BioComFold (Morcher), and AT-45 Crystalens (eyeonics, Inc.). We present a meta-analysis of the peer-reviewed data from studies of these IOLs that use optic-shift measurements and visual acuity as the main outcome measures. In the 6 randomized controlled studies, 5 of which studied the 1CU IOL, the visual acuity results showed moderate to no improvement in near visual acuity compared with control IOLs and a statistically significant but small and inter-patient variable anterior shift of the IOL optic after pilocarpine stimulation. More clinical trials with randomized, controlled, and patient- and examiner-masked study designs that follow the guidelines of evidence-based medicine are needed to prove a benefit of accommodating focus-shift IOLs.

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Methods for assessing forward and backward light scatter in patients with cataract.

J Cataract Refract Surg, 2017; 1072-1076

PURPOSE: To compare objective methods for assessing backward and forward light scatter and psychophysical tests in patients with cataracts.

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

DESIGN: Prospective case series.

METHODS: This study included patients scheduled for cataract surgery. Lens opacities were grouped into predominantly nuclear sclerotic, cortical, posterior subcapsular, and mixed cataracts. Backward light scatter was assessed using a rotating Scheimpflug imaging technique (Pentacam HR), forward light scatter using a straylight meter (C-Quant), and straylight using the double-pass method (Optical Quality Analysis System, point-spread function [PSF] meter). The results were correlated with visual acuity under photopic conditions as well as photopic and mesopic contrast sensitivity.

RESULTS: The study comprised 56 eyes of 56 patients. The mean age of the 23 men and 33 women was 71 years (range 48 to 84 years). Two patients were excluded. Of the remaining, 15 patients had predominantly nuclear sclerotic cataracts, 13 had cortical cataracts, 11 had posterior subcapsular cataracts, and 15 had mixed cataracts. Correlations between devices were low. The highest correlation was between PSF meter measurements and Scheimpflug measurements (r = 0.32). The best correlation between corrected distance visual acuity was with the PSF meter (r = 0.45).

CONCLUSIONS: Forward and backward light-scatter measurements cannot be used interchangeably. Scatter as an aspect of quality of vision was independent of acuity. Measuring forward light scatter with the straylight meter can be a useful additional tool in preoperative decision-making.

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Misalignment of a novel single-piece acrylic intraocular lens in the first three months after surgery.

Ophthalmic Res., 2014; 104-8

PURPOSE: To evaluate the misalignment of a new single-piece microincisional hydrophobic acrylic intraocular lens (IOL) in emmetropic, myopic and hyperopic eyes within the first 3 months after surgery.

SETTING: Vienna Institute for Research in Ocular Surgery, Karl Landsteiner Institute, Hanusch Hospital, Department of Ophthalmology, Vienna, Austria.

METHODS: Patients with age-related cataract were included in this prospective study. Each patient received a single-piece microincisional hydrophobic acrylic IOL (AF-1 NY-60, Hoya) in the study eye. Subgroups of emmetropic, myopic and hyperopic eyes were defined according to IOL power calculation. Anterior chamber depth (ACD) measurements were performed with an AC-Master. Tilt and decentration of the IOL were measured with a Purkinje meter. Follow-up assessments were performed 1 h, 3 weeks and 3 months after surgery.

RESULTS: Forty-two eyes of 42 patients (21 emmetropic, 10 myopic and 11 hyperopic eyes) were included. The mean ACD 1 h, 3 weeks and 3 months after surgery was 4.597 ± 0.533, 4.483 ± 0.347 and 4.438 ± 0.398 mm, respectively. Differences in ACD between follow-ups and between subgroups were not statistically significant (both p > 0.05). On average, 3 months after surgery IOLs were tilted 0.81 ± 2.86° nasally and 0.70 ± 3.13° inferiorly and decentered 0.06 ± 0.24 mm nasally and 0.15 ± 0.29 mm superiorly. Differences in tilt and decentration were not statistically significant (both p > 0.05). We observed 1 case of severe capsular fibrosis.

CONCLUSIONS: The single-piece microincisional hydrophobic acrylic IOL showed good axial stability and only little, clinically not relevant tilt and decentration in the first 3 months after surgery.

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Morphological appearance and size of contact zones of piggyback intraocular lenses.

J Cataract Refract Surg, 2001; 219-23

PURPOSE: To characterize the morphology, size, and change in size of the contact zone of piggyback intraocular lenses (IOLs) of different materials and optic designs.

SETTING: Department of Ophthalmology, Vienna General Hospital, Vienna, Austria.

METHODS: In a prospective study, 9 eyes of 7 patients received piggyback IOLs of the following materials: poly(methyl methacrylate) (PMMA), acrylic, hydrogel, and silicone. The contact zone between the anterior and posterior IOLs was photodocumented from 1 day to 1 year after surgery using specular microscopy. The contact zone area was measured.

RESULTS: A contact zone was present with all IOL materials studied. The area of contact, however, differed significantly. With PMMA IOLs, the contact zone was small and surrounded by Newton rings, indicating the tiny gap between the IOLs. With IOLs of soft material, such as silicone and hydrogel, it was larger than with PMMA IOLs and had a slightly irregular shape. With foldable acrylic IOLs, it was regular, round, and slightly larger than with the soft materials. The contact area enlarged primarily during the first 3 months after surgery. After 1 year, 2 eyes with acrylic piggyback IOLs had a membrane formation around the contact zone and 2 eyes developed Elschnig pearls between the IOLs.

CONCLUSION: In piggyback IOL eyes, the shape and size of the contact zone were strongly dependent on the IOL material and optic design. Contact area enlargement seemed to be induced by capsule shrinkage. Fibrous membrane formation around the contact zone and Elschnig pearl formation between the piggyback IOLs were long-term complications of this technique.

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Multifocal toric intraocular lenses versus multifocal intraocular lenses combined with peripheral corneal relaxing incisions to correct moderate astigmatism.

J Cataract Refract Surg, 2014; 1625-32

PURPOSE: To compare the outcomes of multifocal toric intraocular lens (IOL) implantation and standard nontoric multifocal IOL implantation combined with peripheral corneal relaxing incisions (PCRIs) in patients with moderate preexisting corneal astigmatism.

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

DESIGN: Prospective randomized controlled trial.

METHODS: Patients with visually significant cataract in both eyes who desired spectacle independence and had corneal astigmatism (1.00 to 2.50 diopters [D]) had multifocal toric IOL implantation in 1 eye and a nontoric multifocal IOL combined with PCRIs (Donnenfeld nomogram) in the contralateral eye. Outcome measures were visual acuity, astigmatic vector reduction, digital toric IOL axis determination, spectacle need, and patient satisfaction.

RESULTS: Thirty patients were enrolled. Three months postoperatively, the mean residual refractive astigmatism was 0.45 D ± 0.49 (SD) in the toric IOL group and 0.72 ± 0.61 D in the PCRI group. The mean uncorrected distance visual acuity was 0.10 ± 0.14 in the toric IOL group and 0.15 ± 0.14 in the PCRI group and the mean uncorrected near visual acuity, 0.43 ± 0.11 and 0.39 ± 0.10, respectively. The mean absolute misalignment from the intended axis was 2.52 ± 1.97 degrees. The rotation was within ±3 degrees in 90.9% of all cases and within ±6 degrees in all cases. On the questionnaire, 52.9% of all patients said they required spectacles only when reading for a long time.

CONCLUSION: Although refractive astigmatism decreased in both groups, multifocal toric IOL implantation was predictable with good rotational stability.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

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Natural course of Elschnig pearl formation and disappearance.

Invest. Ophthalmol. Vis. Sci., 2010; 1547-53

PURPOSE: To observe and analyze the daily and weekly changes in morphology and size of Elschnig pearls in eyes with after-cataract.

METHODS: Pseudophakic eyes with pronounced regeneratory posterior capsule opacification (PCO) were included in this prospective study. High-resolution retroillumination images were taken, and the changes in size and shape of Elschnig pearls were analyzed at baseline and at 2, 7, and 14 days later using dedicated imaging software.

RESULTS: In total, 6309 Elschnig pearls in 85 eyes of 77 patients were analyzed. On average, four pearls were found per square millimeter (range, 0.2-9.7/mm(2); CV, 49.5%) with a mean cumulative area of 0.66 mm(2) (range, 0.03-2.18 mm(2); CV, 66.7%) of all marked pearls per eye and follow-up, which was 3.8% of the analyzed area. The mean pearl size was 9630 microm(2) (range, 2390-33,745 microm(2); CV, 61.0%) at baseline, which corresponded to a diameter of 174 microm. The mean change of a pearl per day was 583 microm(2) (range, 175-1631 microm(2); CV, 55.4%) or a 6% change in area. In total, 36% (CV, 5.5%) of all pearls increased in size, 7% (CV, 8.6%) did not change, and 35% (CV, 6.7%) decreased in size during 1 week. Furthermore, 11% (CV, 6,3%) of all pearls newly appeared, and the same number disappeared (CV, 5.7%) within 1 week.

CONCLUSIONS: Elschnig pearls disappear and appear within days. The degree of progression and regression varies greatly between eyes. Knowledge about Elschnig pearl turnover may be of importance for attempts to modulate lens epithelial regeneration or lens regrowth and for lens-refilling procedures.

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Natural course of intraocular pressure after cataract surgery with sodium chondroitin sulfate 4%-sodium hyaluronate 3% (Viscoat).

Ophthalmology, 2005; 1714-8

PURPOSE: To investigate the natural course of intraocular pressure (IOP) and its peak after small-incision cataract surgery with chondroitin sulfate 4%-sodium hyaluronate 3% (Viscoat, Alcon Laboratories, Inc., Fort Worth, TX).

DESIGN: Observational case series.

PARTICIPANTS: This prospective study comprised 40 eyes of 40 consecutive cataract patients scheduled for small-incision cataract surgery.

METHODS: Cataract surgery was performed with sodium chondroitin sulfate 4%-sodium hyaluronate 3% as the ophthalmic viscosurgical device, which was removed as completely as possible from the eye at the end of surgery. The IOP was measured preoperatively and 30 minutes; 1, 2, 3, 4, 6, 8, and 20 to 24 hours; and 1 week postoperatively.

MAIN OUTCOME MEASURES: Postoperative IOP increase.

RESULTS: The mean IOP increased significantly at all observation times during the first 20 to 24 hours, with a peak increase of 13.4+/-9.4 mmHg after 1 hour (P<0.05). In all, 28 eyes (70%) had an IOP spike to 30 mmHg or higher. Sixty-eight percent of these spikes occurred at 30 minutes as well as at 1 hour and 2 hours postoperatively. At 20 to 24 hours, no eye had an IOP spike to 30 mmHg or higher.

CONCLUSIONS: Significant IOP increases were found during the first 24 hours, peaking at 1 hour after surgery. With a single postoperative IOP measurement, between 30 minutes and 2 hours after surgery, two thirds of these IOP spikes could be detected. To detect all IOP spikes, a second measurement between 4 and 6 hours after surgery would be necessary.

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Natural course of intraocular pressure after cataract surgery with sodium hyaluronate 1% versus hydroxypropylmethylcellulose 2%.

Ophthalmology, 2007; 1089-93

PURPOSE: To investigate the natural course of intraocular pressure (IOP) after small-incision cataract surgery with sodium hyaluronate 1% versus hydroxypropylmethylcellulose 2%.

DESIGN: Randomized clinical trial.

PARTICIPANTS: Eighty eyes of 40 consecutive patients with bilateral age-related cataract.

METHODS: The patients were assigned randomly to receive sodium hyaluronate 1% or hydroxypropylmethylcellulose 2% during cataract surgery in the first eye. The second eye received the other ophthalmic viscosurgical device. The IOP was measured preoperatively and 30 minutes; 1, 2, 3, 4, 6, 8, and 20 to 24 hours; and 1 week postoperatively.

MAIN OUTCOME MEASURE: Postoperative IOP increase.

RESULTS: The highest mean IOP increase occurred at 8 hours postoperatively (5.3+/-6.4 mmHg) in the sodium hyaluronate 1% group and at 2 hours postoperatively (7.8+/-6.1 mmHg) in the hydroxypropylmethylcellulose 2% group. Overall, the IOP increase was higher with hydroxypropylmethylcellulose 2% (P = 0.005). Intraocular pressure spikes to > or =30 mmHg occurred in 5 eyes (13%) in the sodium hyaluronate 1% group and 13 eyes (33%) in the hydroxypropylmethylcellulose 2% group.

CONCLUSIONS: Sodium hyaluronate 1% and hydroxypropylmethylcellulose 2% caused significant IOP increases during the first 8 hours after cataract surgery. A single measurement at 6 hours postoperatively could detect all IOP spikes in the sodium hyaluronate 1% group. In the hydroxypropylmethylcellulose 2% group, a single measurement at 2 hours postoperatively could detect two thirds of IOP spikes.

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Natural course of posterior subcapsular cataract over a short time period.

Curr. Eye Res., 2017; 1604-1607

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MATERIALS AND METHODS: Thirty-six eyes of 36 patients with pronounced PSC were included in this prospective study. High-resolution retroillumination images were taken, and the changes in size and shape of Wedl cells were analyzed at baseline and at 2 and 4 weeks later using dedicated imaging software.

RESULTS: In total, 1087 Wedl cells were observed. Within 2 and 4 weeks, 31 and 22 Wedl cells appeared and 13 and 40 Wedl cells disappeared, respectively. Median Wedl cell size at baseline and after 2 and 4 weeks was 4000 µm (range: 40-212120 µm), 4080 µm (range: 40-274520 µm), and 4160 µm (range: 40-212200 µm), respectively. For the absolute size change within 4 weeks, a significant difference was observed (p = 0.045). The median change in absolute solidity within 2 and 4 weeks was 0.01 (range: 0.00-0.19) and 0.02 (range: 0.00-0.53), respectively.

CONCLUSIONS: Wedl cells undergo morphological changes within a short time period of 4 weeks and even appearance and disappearance of Wedl cells can be observed within weeks. The fact that spontaneous regression occurs may, when properly understood, have some relevance for the development of therapeutical approaches to reverse existing PSC in the future.

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Nitric oxide and ocular blood flow in patients with IDDM.

Diabetes, 1997; 653-8

Endothelial dysfunction has been implicated in the pathogenesis of diabetic vascular disorders such as diabetic retinopathy. We hypothesized that either local endogenous nitric oxide (NO) synthesis or local reactivity to endogenous NO might be impaired in patients with IDDM and that this may contribute to the development of diabetic retinopathy. Ten otherwise healthy patients with long-standing IDDM and ten healthy control subjects were studied according to an open randomized two-way cross-over design. Subjects received intravenous infusions of either N(G)-monomethyl-L-arginine, an inhibitor of NO-synthase, or L-arginine, the precursor of NO synthesis, on two separate study days. Ocular hemodynamics were assessed by laser interferometric measurement of fundus pulsations and Doppler sonographic measurement of blood flow velocity in the ophthalmic artery. N(G)-monomethyl-L-arginine decreased fundus pulsations and blood flow velocity in the ophthalmic artery and increased blood pressure in healthy subjects. The responses to NO-synthase inhibition were significantly less in diabetic subjects. In contrast, L-arginine caused a comparable increase in fundus pulsations and decrease in blood pressure in both cohorts. These results indicate that systemic and ocular hemodynamic reactivity to NO-synthase inhibition is reduced in patients with long-standing IDDM, compared with healthy control subjects. Thus, this study indicates that either NO-synthase activity is increased or NO sensitivity is decreased in patients with IDDM and supports the concept of an involvement of the L-arginine-NO system in the pathophysiology of diabetic retinopathy.

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Nitric oxide synthase inhibition in the histamine headache model.

Cephalalgia, 1997; 175-82

Histamine has been widely used experimentally to induce headache in healthy subjects and migraine in migraineurs. There is evidence that the vascular effects of histamine are at least partially mediated by nitric oxide (NO). Hence we hypothesized that subjective symptoms and hemodynamic effects of histamine could be reduced by systemic NO-synthase inhibition. We therefore studied the effect of pretreatment with N-monomethyl-L-arginine (L-NMMA), a competitive inhibitor of NO-synthase, or placebo on headache, flush and discomfort scores during histamine infusion. Additionally, blood flow velocities in the middle cerebral and the ophthalmic artery and ocular fundus pulsations were measured. Whereas L-NMMA blunted the effect of histamine in the ophthalmic artery and the ocular circulation, NO-synthase inhibition did not mitigate subjective symptoms. Histamine did not affect mean blood flow velocities in the middle cerebral artery. Hence, we conclude that NO-synthase inhibition reduces the histamine-induced vascular effects in the ocular circulation, but is not sufficient to attenuate or abort the subjective symptoms provoked by histamine infusion.

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Noninvasive investigations of the normal ocular circulation in humans.

Invest. Ophthalmol. Vis. Sci., 1998; 1210-20

PURPOSE: To compare the reproducibility of laser interferometric measurements of fundus pulsation, pneumatonometric measurement of pulse amplitude (PA) and pulsatile ocular blood flow (POBF), and Doppler ultrasonic measurements of blood flow velocity in the ophthalmic artery (OA) and the posterior ciliary arteries (PCAs) and to investigate the association of the results obtained with these methods and to characterize ocular hemodynamics during Valsalva maneuver and isometric handgrip.

METHODS: All studies were performed in healthy subjects. Fundus pulsation (n = 48), POBF (n = 24), and blood flow velocities (n = 24) were measured at baseline and during the Valsalva maneuver and isometric handgrip. Intraclass correlation coefficients were calculated for test/retest variability, for short-term variability, and for interobserver variability.

RESULTS: Intraclass correlation coefficients were between 0.95 and 0.98 for fundus pulsation measurements, between 0.54 and 0.76 for pneumatonometric measurements, between 0.44 and 0.88 for Doppler sonographic measurements in the OA and between 0.32 and 0.60 in the PCAs. There was a high degree of association between pneumatonometric parameters and fundus pulsation amplitude. Valsalva maneuver significantly reduced fundus pulsations, PA, and POBF, whereas isometric handgripping did not change these parameters.

CONCLUSIONS: The reproducibility of fundus pulsation measurements was excellent. Reproducibility of pneumatonometric parameters and ultrasonographic measurements in the OA was satisfactory. Reproducibility of ultrasonographic measurements in the PCAs was low. Data obtained during the autonomic stimuli experiments argue against the sole use of systems to measure pulsatile blood flow, if no additional data on flow pulsatility are available. At least in cases when changes in blood pressure are likely to occur the ratio of pulsatile to nonpulsatile blood flow might not be constant and POBF might not be an adequate measure of total ocular blood flow.

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Ocular and systemic reactivity to isoprenaline in patients with insulin-dependent diabetes mellitus.

Eur. J. Clin. Invest., 1997; 750-4

There is experimental evidence of decreased beta-adrenergic myocardial sensitivity in patients with insulin-dependent diabetes mellitus (IDDM). In the present study we hypothesized that the ocular response to isoprenaline, as a consequence of increased arterial vessel rigidity, might also be blunted in patients with IDDM. We therefore compared the correlation between systemic pulse pressure amplitude (PPA) and fundus pulsation amplitude (FPA) during intravenous isoprenaline administration in 11 otherwise healthy IDDM patients and 11 healthy control subjects. Ocular fundus pulsations were measured by a recently developed laser interferometric method. Isoprenaline increased PPA in both study groups in a dose-dependent way, but the response was significantly less in IDDM patients (at 0.8 microgram min-1: +38% in control subjects, +27% in IDDM patients, P < 0.05 between groups). Moreover, a dose-dependent increase in FPA was observed, which again was more pronounced in healthy subjects (at 0.8 microgram min-1: +45% in controls, +17% in IDDM patients, P < 0.005 between groups). The regression line between PPA and FPA was very close to the 45 degrees line in healthy subjects, whereas it was significantly flattened in IDDM patients. In conclusion, linear regression between PPA and FPA during isoprenaline suggests arterial stiffening in patients with IDDM. Hence, comparison of systemic PPA and FPA during isoprenaline provocation may be a useful method of estimating changes in arterial capacitance in patients with diabetes mellitus.

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Ocular haemodynamics and colour contrast sensitivity in patients with type 1 diabetes.

Br J Ophthalmol, 2000; 493-8

BACKGROUND: There is evidence that altered ocular blood flow is involved in the development and progression of diabetic retinopathy. However, the nature of these perfusion abnormalities is still a matter of controversy. Ocular haemodynamics were characterised with two recently introduced methods.

METHODS: The cross sectional study was performed in 59 patients with type 1 diabetes with a diabetes duration between 12 and 17 years and an age less than 32 years and a group of 25 age matched healthy controls. Scanning laser Doppler flowmetry and laser interferometric measurement of fundus pulsation amplitude were used to assess retinal and pulsatile choroidal blood flow, respectively. In addition, colour contrast sensitivity along the tritan axis was determined.

RESULTS: Fundus pulsation amplitude, but not retinal blood flow, increased with the progression of diabetic retinopathy. Retinal blood flow was influenced by plasma glucose levels (r = 0.32), whereas fundus pulsation amplitude was associated with HbA(1c) (r = 0.30). In addition, a negative correlation between the colour contrast sensitivity along the tritan axis and retinal blood flow was observed.

CONCLUSIONS: The present study indicates that pulsatile choroidal blood flow increases with the progression of diabetic retinopathy. Increased retinal blood flow appears to be related to loss of colour sensitivity in patents with type 1 diabetes.

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Ocular hemodynamics during isometric exercise.

Microvasc. Res., 2001; 1-13

The autoregulatory capacity of the human retina is well documented, but the pressure-flow relationship of the human choroid is still a matter of controversy. Recent data, using laser Doppler flowmetry to measure choroidal blood flow, indicate that the choroid has some autoregulatory potential, whereas most data using other techniques for the assessment of choroidal hemodynamics indicate that the choroidal pressure-flow curve is linear. We used a new laser interferometric technique to characterize choroidal blood flow during isometric exercise. Twenty healthy subjects performed squatting for 6 min during normocapnia and during inhalation of 5% CO2 and 95% air. Ocular fundus pulsation amplitude, flow velocities in the ophthalmic artery, intraocular pressure, and systemic hemodynamics were measured in 2-min intervals. To gain information on choroidal blood flow fundus pulsation amplitude was corrected for changes in flow pulsatility using data from the ophthalmic artery and for changes in pulse rate. Ocular perfusion pressure was calculated from mean arterial pressure and intraocular pressure. The ocular pressure-flow relationship was calculated by sorting data according to ascending ocular perfusion pressure values. In a pilot study in 6 healthy subjects comparable ocular pressure flow relationships were obtained when choroidal blood flow was assessed with the method described above and with laser Doppler flowmetry. In the main study isometric exercise caused a significant increase in mean arterial pressure (56%, P < 0.001), pulse rate (84%, P < 0.001), and intraocular pressure (37%, P 0.004), but decreased fundus pulsation amplitude (-36%, P < 0.001). Significant deviations from baseline choroidal blood flow were observed only at ocular perfusion pressures >69% during normocapnia and 70% during hypercapnia. Our data indicate that during isometric exercise the choroid has a high capacity to keep blood flow constant despite changes in perfusion pressure and that this pressure-flow relationship is not altered by moderate changes in arterial carbon dioxide levels.

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Optical biometry in cataract surgery.

Dev Ophthalmol, 2002; 131-40

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Optical biometry of the anterior eye segment: interexaminer and intraexaminer reliability of ACMaster.

J Cataract Refract Surg, 2005; 2334-9

PURPOSE: To evaluate the interexaminer and intraexaminer reliability of corneal thickness, anterior chamber depth (ACD), and crystalline lens thickness measurements using a commercially available anterior segment optical biometry instrument (ACMaster, Carl Zeiss Meditec) based on partial coherence interferometry (PCI).

SETTING: Medical University of Vienna, Vienna, Austria.

METHODS: Interexaminer reliability and intraexaminer reliability were evaluated in 10 eyes of 10 young volunteers and 11 eyes of 11 cataract patients. The measurements of the interexaminer reliability were taken by 3 examiners. Corneal thickness, ACD, and lens thickness of the intraexaminer reliability were measured twice in all eyes by 1 examiner. To evaluate the effect of cycloplegia on the variability, the measurements were performed on 5 volunteers under cyclopentolate 1%. Measurements were performed using the prototype of the ACMaster based on PCI.

RESULTS: The interexaminer/intraexaminer reliabilities were 99.9% for corneal thickness and ACD. The reliability of lens thickness could not be estimated because of a large number of missing values in the cataract patient group. The median interexaminer variability (SD) was 1.9 microm for corneal thickness, 7.5 microm for ACD, and 10.6 microm for lens thickness. The median intraexaminer variability (SD) was 1.6 microm for corneal thickness, 10.8 microm for ACD, and 8.7 microm for lens thickness. With cycloplegia, both the interexaminer variability and intraexaminer variability were smaller than without cycloplegia.

CONCLUSIONS: Partial coherence interferometry measurements of anterior chamber distances (corneal thickness, ACD, lens thickness) using the prototype of ACMaster were highly reliable, allowing examiner-independent measurements. However, lens thickness measurements in cataract eyes were often difficult.

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Optical coherence tomography assessment of capsule closure after cataract surgery.

J Cataract Refract Surg, 2005; 330-6

PURPOSE: To develop a technique for documenting and quantifying capsule bend formation in pseudophakic eyes, evaluate when the anterior and posterior lens capsules become completely apposed to the optic, and determine how soon a capsule bend is created at the optic edge of an intraocular lens (IOL) after cataract surgery.

SETTING: Medical University of Vienna, Department of Ophthalmology, Vienna, Austria.

METHODS: This prospective study comprised 33 eyes of 33 patients with age-related cataract who were scheduled to have cataract surgery. All eyes had phacoemulsification with implantation of 1 of 3 types of open-loop IOLs: 1-piece acrylic (SA60AT, Alcon), 3-piece acrylic (AcrySof MA60BM, Alcon), or 3-piece silicone (911A, AMO). Each group included 11 eyes. One and 3 days and 1, 2, 3, and 4 weeks after surgery, contact between the lens capsule and IOL optic as well as capsule bend formation were evaluated using optical coherence tomography (OCT). The postoperative times at which the capsule came into contact with the IOL optic and when the capsule bend formed were determined.

RESULTS: One day postoperatively, the mean distance between the anterior capsule and the IOL was 197 microm in the 1-piece acrylic IOL group, 161 microm in the 3-piece acrylic IOL group, and 220 microm in the 3-piece silicone IOL group. The posterior capsule was in contact with the IOL on the same day or earlier than the anterior capsule in 28 patients (85%). Postoperatively, the capsule bend formed at a mean of 10 days in the 1-piece acrylic group, 13 days in the 3-piece acrylic group, and 15 days in the 3-piece silicone group. The short-term reproducibility of the OCT technique was excellent (r = 0.99).

CONCLUSIONS: Optical coherence tomography produced cross-sectional tomograms of capsule-IOL contact in the early postoperative period. There was no significant difference in the time to capsule bend formation between the 3 IOLs. However, capsule bend formation at the optic edge occurred earlier with the 1-piece acrylic IOL than with the 3-piece silicone IOL.

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Partial coherence interferometry: a novel approach to biometry in cataract surgery.

Am. J. Ophthalmol., 1998; 524-34

PURPOSE: To compare biometry performed by an enhanced version of dual beam partial coherence interferometry and applanation ultrasound in a prospective study of 85 cataract eyes to improve refractive outcome of cataract surgery due to a more accurate calculation of intraocular lens power.

METHODS: The SRK II formula using ultrasound biometry data was employed. Three months after surgery, partial coherence interferometry biometry was repeated and refractive outcome was determined. Preoperative partial coherence interferometry biometry data were used to determine the refractive power of the intraocular lenses retrospectively and to calculate the possible refractive outcome.

RESULTS: Precision of partial coherence interferometry biometry was more than 10 times better than that of ultrasound. Therefore, the possible mean absolute error for postoperative refraction achieved with partial coherence interferometry biometry was 0.49 diopters (compared with 0.67 diopters with ultrasound biometry), resulting in an improvement of 27%. Axial eye length measured with the two techniques differed by a mean of 460 microm. The difference in lens thickness measured with partial coherence interferometry and ultrasound significantly correlated with cataract grade. A mean shortening of 120 microm of axial eye length following cataract surgery was also detected by partial coherence interferometry.

CONCLUSIONS: The enhanced version of partial coherence interferometry offers biometry with unprecedented precision (<10 microm) and resolution (approximately 12 microm), therefore improving the refractive outcome in cataract surgery. This noninvasive technique provides a high degree of comfort for the patient, with no need for local anesthesia or pupil dilation and minimized risk of corneal infection.

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Pharmacokinetics of Caffeine in the Lens Capsule/Epithelium After Peroral Intake: A Pilot Randomized Controlled Study.

Invest. Ophthalmol. Vis. Sci., 2018; 1855-1860

Purpose: To determine the pharmacokinetics of perorally administered caffeine, a widely consumed and potent dietary antioxidant, in the anterior lens capsule and lens epithelial cells, a crucial cell monolayer for cataract development.

Methods: Bilateral cataract patients were scheduled for cataract surgery with a caffeine abstinence of 1 week before surgery of each eye. At the day of surgery of the second eye patients were administered no drink (0-mg group) or coffee with 60-, 120-, or 180-mg caffeine. After capsulorhexis the lens capsule including lens epithelial cells was transferred to a test tube for analysis of caffeine concentration by gas chromatography-mass spectrometry (GC-MS/MS).

Results: Coffee consumption significantly (P < 0.05) increased caffeine levels of the lens capsule/epithelium in the 60-, 120-, and 180-mg group. Caffeine concentrations (caffeine ng/lens capsule/epithelium) measured as difference between 1st and 2nd eye were -0.52 ± 1.16 (0-mg group, n = 7), 1.88 ± 2.02 (60-mg group, n = 8), 2.09 ± 0.67 (120-mg group, n = 9), and 3.68 ± 1.86 (180-mg group, n = 9). The increase constant of caffeine in a linear regression model was estimated as a 95% CI 0.02 ± 0.0046 (degrees of freedom; 25; r = 0.85).

Conclusions: Peroral intake of coffee significantly increased caffeine concentrations in the lens capsule and lens epithelial cells in a dose-dependent manner. This information is important for further investigations on preventing cataract.

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Piggyback intraocular lenses.

J Cataract Refract Surg, 2000; 308-9

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Pilocarpine-induced shift of an accommodating intraocular lens: AT-45 Crystalens.

J Cataract Refract Surg, 2005; 1290-7

PURPOSE: To measure the shift of an accommodating plate-haptic intraocular lens (IOL) along the visual axis induced by ciliary muscle contraction after application of pilocarpine.

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: Fifty-four eyes of 28 patients with age-related cataract comprised this prospective study. Each patient received an AT-45 silicone accommodating IOL (Crystalens, Eyeonics Corp.) after standardized cataract surgery. In a subgroup of 24 eyes, capsular bag fibrosis was reduced by extensive polishing of the anterior capsule with a slit cannula. Assessment included measurements of anterior chamber depth, assessed with partial coherence interferometry, before and after application of pilocarpine 2% and evaluation of near visual acuity 1 month and 3 months postoperatively.

RESULTS: A slight backward shift of the IOL of 151 mum in the nonpolished group (P < .001) and 122 mum in the polished group (P < .005) could be detected after application of pilocarpine. Polishing the capsule did not influence IOL shift. The median near visual acuity with distance correction 1 month and 3 months postoperatively was J5 and J4, respectively, in the nonpolished group and J6 at both times in the polished group.

CONCLUSIONS: Pilocarpine induced a counterproductive active backward shift of the AT-45 IOL. Polishing of the capsular bag had no impact on accommodative ability. The reading performance of patients with the AT-45 IOL patients at 1 and 3 months was not significantly different from that of with a standard IOL under similar testing methods.

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Posterior capsule opacification and capsular bag performance of a microincision intraocular lens.

J Cataract Refract Surg, 2011; 1988-92

PURPOSE: To assess the axial stability and posterior capsule opacification (PCO)-inhibiting efficacy of a microincision hydrophilic intraocular lens (IOL) (Idea 613 XC) and a standard hydrophobic open-loop acrylic IOL (Acrysof SA60AT).

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

DESIGN: Clinical trial.

METHODS: Patients with bilateral cataract received a microincision cataract surgery (MICS) IOL in 1 eye and a small-incision cataract surgery (SICS) IOL in the contralateral eye. Follow-up examinations were performed immediately after surgery and postoperatively at 1 week and 3 and 24 months. Posterior capsule opacification was assessed using retroillumination photography. Anterior chamber depth (ACD) was measured using partial coherence laser interferometry, and IOL tilt and decentration were measured using a Purkinje meter.

RESULTS: Seventy eyes (35 patients) were enrolled. The mean ACD at 3 months was 4.91 mm ± 0.26 (SD) in the MICS group and 4.60 ± 0.23 mm in the SICS group. The anterior IOL shift over the first 3 months was slightly smaller with the MICS IOL (81 μm) than with the SICS IOL (254 μm). The mean ACD was 0.377 ± 178 μm deeper with the MICS IOL (P<.01, paired t test). Two years postoperatively, the amount of regeneratory PCO was higher with the MICS IOL than with the SICS IOL (image analysis software score 2.6 versus 1.9; P=.005).

CONCLUSIONS: Two years after surgery, the PCO rate was slightly higher with the MICS IOL. The 2 IOLs had similar performance in terms of axial stability, decentration, and tilt.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes.

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Posterior capsule opacification in silicone and hydrophobic acrylic intraocular lenses with sharp-edge optics six years after surgery.

Am. J. Ophthalmol., 2009; 683-690.e2

PURPOSE: To compare posterior capsule opacification (PCO) between 2 three-piece intraocular lenses (IOLs) both with sharp-optic edges and open loop haptics, one made of silicone and the other made of hydrophobic acrylate, 6 years after surgery.

DESIGN: Randomized, controlled, patient- and examiner-masked trial with intra-patient comparison.

METHODS: One hundred and six eyes in 53 patients were included initially. Forty-four eyes of 22 patients with age-related bilateral cataract were available for the 6 years follow-up. Each patient had standard cataract surgery and randomly received a silicone (CeeOn 911A; AMO, Santa Ana, California, USA) or hydrophobic acrylic (AcrySof MA60BM; Alcon, Fort Worth, Texas, USA) IOL in the first eye, the other type of IOL in the fellow eye. Follow-up examinations were at 1, 3, and 6 years after surgery. The intensity of posterior capsule opacification (PCO) was assessed using digital retro-illuminated photos and the "automated quantification of after-cataract" (AQUA) software. Neodymium-yttrium-aluminum-garnet-laser capsulotomies (YAG-LC) performed were noted.

RESULTS: Six years after surgery, the AQUA scores were 2.3 +/- 1.4 for the silicone and 3.8 +/- 2.0 for the acrylic IOLs (P = .0016). The acrylic IOL eyes also had a significant increase in AQUA score from the 3-year to the 6-year follow-up. YAG-LC were performed in 2 silicone and 6 acrylic IOLs (P = .01).

CONCLUSIONS: An angulated three-piece hydrophobic acrylic IOL had more PCO 6 years after surgery than a silicone IOL of otherwise similar design. Apart from an optic material effect, differences in haptic design and the degree of optic edge sharpness may play a role.

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Posterior continuous curvilinear capsulorhexis with hydrogel and silicone intraocular lens implantation: development of capsulorhexis size and capsule opacification.

J Cataract Refract Surg, 2001; 825-32

PURPOSE: To evaluate the influence of primary posterior continuous curvilinear capsulorhexis (PCCC) on capsule opacification development and capsular bag changes within the first year after cataract surgery with 2 intraocular lenses (IOLs) of comparable design but different material.

SETTING: Department of Ophthalmology, University of Vienna, Medical School, Vienna, Austria.

METHODS: Thirty-seven patients with age-related cataract had bilateral small incision cataract surgery with a PCCC performed after capsular tension ring insertion. One eye was randomly assigned to receive a hydrogel IOL and the other eye, a silicone IOL. Standardized digital retroillumination photographs were taken 1 day, 1 week, and 1, 3, 6, and 12 months after surgery to evaluate changes in the dimensions of the anterior and posterior capsulorhexis opening area and the presence of anterior and posterior capsule opacification.

RESULTS: The area of the anterior continuous curvilinear capsulorhexis (ACCC) opening was significantly reduced during the first 6 postoperative months. The shrinkage was more pronounced (-25%) in the silicone IOL group than in the hydrogel IOL group. Ten percent of eyes with a silicone IOL had marked shrinkage of the ACCC. The area of the PCCC did not change in eyes with a hydrogel IOL but was larger (+20%) in eyes with a silicone IOL. Anterior ongrowth was observed in 60% in the hydrogel group and in no eye in the silicone group. Anterior capsule fibrosis was observed in 90% in the silicone group and in 20% in the hydrogel group. Total closure of the PCCC was not observed within the first year, but posterior ongrowth was observed in 40% in the hydrogel group and 10% in the silicone group.

CONCLUSIONS: Anterior capsulorhexis shrinkage with concomitant posterior capsulorhexis enlargement was observed in eyes with a silicone IOL. The hydrogel IOL induced more ongrowth on the anterior and posterior IOL surfaces, whereas the silicone IOL induced more anterior capsule fibrosis. Total closure of the PCCC was not observed within the first year after surgery.

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Postoperative change in effective lens position of a 3-piece acrylic intraocular lens.

J Cataract Refract Surg, 2003; 1974-9

PURPOSE: To study the change in postoperative position of an angulated, 3-piece, foldable acrylic intraocular lenses (IOLs) and evaluate the effect of a sharp posterior optic edge compared with that of a round optic edge on the change in postoperative anterior chamber depth (ACD).

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: This randomized intraindividual-comparison study comprised 104 eyes of 52 patients with age-related cataract. Patient received a sharp-edged Sensar OptiEdge AR40e IOL (Allergan Surgical) in 1 eye and a round-edged Sensar AR40 IOL in the other eye. Postoperative follow-up included ACD measurement by partial coherence interferometry and evaluation of the capsulorhexis area by standardized retroillumination photography at 1 day, 1 week, and 1 and 6 months.

RESULTS: A decrease in ACD during the first postoperative week was followed by a small increase in ACD during the first 6 months. There was no significant difference between the sharp-edged group and the round-edged group.

CONCLUSIONS: The angulated 3-piece acrylic IOLs showed significant forward movement over the first postoperative 6 months. Although the change in refraction was small, there was variability among patients. The sharp posterior optic edge design did not affect the IOL's movement in the capsular bag.

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Postoperative inflammation after clear corneal and sclerocorneal incisions.

J Cataract Refract Surg, 1998; 524-8

PURPOSE: To compare two standard small incision techniques for cataract surgery--clear corneal incision and sclerocorneal incision--with regard to postoperative disturbance of the blood-aqueous barrier (BAB).

SETTING: Department of Ophthalmology, University of Vienna, Austria.

METHODS: This prospective comparative study comprised 108 eyes with senile cataract. A clear corneal tunnel incision was made in 53 eyes and a sclerocorneal incision with tunnel preparation in 55. All other surgical procedures and postoperative medication were standardized. Postoperative BAB disruption was measured with a laser flare-cell meter (Kowa FC 1000) in an undilated pupil on 1, 3, 7, 14, 28, 60, and 90 days postoperatively. The values were compared using a two-sided t-test.

RESULTS: In both groups, flare and cell values were highest on the first postoperative day. They gradually declined but without recovery of preoperative flare values on day 28. At no time was there a noticeable between-group difference in mean cell and flare values except for flare at day 14 (P = .04).

CONCLUSION: Postoperative trauma, measured by the BAB disturbance, was equally low after clear corneal and sclerocorneal incisions.

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Predicting Lens Diameter: Ocular Biometry With High-Resolution MRI.

Invest. Ophthalmol. Vis. Sci., 2015; 6847-54

PURPOSE: The aim of this study was to correlate different biometric dimensions of the eye as measured from ocular magnetic resonance imaging (MRI) scans to predict the lens diameter.

METHODS: High-resolution ocular MRI scans of 100 eyes of 100 patients were reviewed. Various anatomical variables of the eye such as the axial length, the globe diameter, and the lens dimensions were measured. Also, the distances between the ciliary sulcus and angle-to-angle were measured. A partial least square (PLS) regression model was built to analyze which variables influence the model regarding the lens dimensions.

RESULTS: Sixty-two eyes of 62 patients were included in the final analysis. The lens diameter ratio (horizontal to vertical) was 0.93 (SD: 0.04; 0.83-1.00). The partial least square regression showed a significant connection (P < 0.001) between the horizontal and vertical diameter. The partial least square regression model that included the globe diameter and the axis length resulted in the best prediction for the horizontal lens diameter. Similar to the horizontal lens diameter, globe diameter was the best predictor for the vertical lens diameter followed by the distance of the ciliary sulcus. White-to-white distance, distance of the ciliary sulcus, and axial eye length were found to have a high influence on the angle-to-angle distance.

CONCLUSIONS: The introduced models may serve as tools to predict the capsular bag biometry in a preoperative setting for cataract surgery or lens refilling procedures.

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Predicting postoperative intraocular lens position and refraction.

J Cataract Refract Surg, 2004; 2077-83

PURPOSE: To predict the postoperative IOL position and refraction as accurately as possible independent of individualization of the parameters.

SETTING: Universitats-Augenklinik, Mainz, Germany, and Vienna, Austria.

METHODS: One patient cohort (189 eyes, Vienna) was used to calibrate the prediction method, which was then applied to a second cohort (65 eyes, Mainz). All calculations were based on consistent numerical ray tracing of the pseudophakic eye using the original manufacturer's intraocular lens (IOL) data (radii, thickness, refractive index). A new algorithm to predict IOL position was developed. Ultrasound (US) axial lengths were calibrated relative to partial coherence interferometry (PCI). Corneal radii extracted from topography were checked against radii measured with the IOLMaster (Zeiss) and by Littmann keratometry.

RESULTS: Zero mean prediction errors for IOL position and refraction were obtained without adjusting the parameters and with PCI lengths or US lengths calibrated relative to the PCI values. There was no significant loss of accuracy of US data compared to PCI data. Corneal radii extracted from topography were slightly but statistically significantly different from the Littmann values, and they were more accurate than the latter with respect to prediction error. The measured mean central IOL position (distance from posterior corneal surface) for all IOL types was 4.580 mm, a value very close to the mean recalculated from A-constants (4.587 mm). The difference in the individual central IOL position relative to the mean value depended only linearly (ie, no higher orders such as square or cubic are needed) on axial length, with the mean central IOL position as a free parameter. This parameter should be 4.6 +/- 0.2 mm (the same value as independently measured or recalculated) to obtain zero steepness of the prediction error as a function of axial length, producing zero bias for long and short eyes.

CONCLUSIONS: Calculation errors from formulas and confusing adjusting parameters can be avoided if calculations and measurements are performed on a clear and simple physical basis. Nevertheless, an individual prediction error, typically 0.5 to 1.0 diopter, seems to be unavoidable.

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Predicting the postoperative intraocular lens position using continuous intraoperative optical coherence tomography measurements.

Invest. Ophthalmol. Vis. Sci., 2013; 5196-203

PURPOSE: The aim of this study was to assess, if measuring the position of the lens capsule intraoperatively with a continuous intraoperative optical coherence tomography (OCT) device could be useful to improve the prediction of the intraocular lens (IOL) position.

METHODS: This prospective study included patients who were scheduled for cataract surgery. A prototype operating microscope with an integrated continuous OCT device was used to measure the anterior and posterior lens capsule position at different time points during cataract surgery. In all cases, a capsular tension ring (CTR) was used to tauten the lens capsule. Partial coherence interferometry was used to measure anterior chamber depth (ACD) immediately before, and 1 hour and 3 months postoperatively. Partial least squares regression (PLSR) was used to assess the influence of different pre- and intraoperatively measured parameters.

RESULTS: In total, 70 eyes of 70 patients were included. Mean axial eye length was 23.6 mm (range, 20.6 mm-30.8 mm), mean used IOL power was 22.2 diopters (D; range, 6.0 D-31.5 D). PLSR showed that the anterior lens capsule measured after removing the crystalline lens and after implanting a CTR was a significantly better predictor for the postoperative ACD compared with preoperative ACD measurements.

CONCLUSIONS: The main problem of IOL power calculation, the prediction of the IOL position after surgery, could possibly be reduced by using intraoperative lens capsule measurements instead of preoperative ACD measurements. (ClinicalTrials.gov number, NCT01867541.).

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Prediction of postoperative intraocular lens tilt using swept-source optical coherence tomography.

J Cataract Refract Surg, 2017; 732-736

PURPOSE: To compare crystalline lens tilt in eyes before and intraocular lens (IOL) tilt in eyes after cataract surgery using swept-source optical coherence tomography (SS-OCT) (IOLMaster 700).

SETTING: Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective case series.

METHODS: Patients' eyes were scanned 1 week before and 2 months after cataract surgery with IOL implantation using an SS-OCT device. This device performs B-scans along 6 meridians (0, 30, 60, 90, 120, and 150 degrees) to determine lens and IOL tilt.

RESULTS: Sixty-two eyes (62 patients) were included in the analysis. The mean magnitude and direction of tilt showed mirror symmetry between both eyes along the vertical axis and a primarily nasal outward tilt for right eyes and left eyes. The mean tilt was 4.3 degrees at 15.8 degrees preoperatively and 6.2 degrees at 16.8 degrees postoperatively. The mean direction of crystalline lens tilt preoperatively and IOL tilt postoperatively showed a strong correlation (R = 0.71), whereas the mean magnitude of tilt showed a weaker correlation (R = 0.37). The direction and magnitude of tilt of the crystalline lens and IOL eyes were normally distributed around similar values before and after surgery.

CONCLUSIONS: The correlations between crystalline lens tilt and IOL tilt using whole-eye scanning indicate that preoperative tilt determination using SS-OCT could help predict postoperative IOL tilt, assist in IOL (toric) power calculations, and potentially improve visual outcomes.

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Prediction of pseudophakic capsular bag diameter based on biometric variables.

J Cataract Refract Surg, 1999; 1376-81

PURPOSE: To measure the capsular bag diameter (CBDm) in vivo and calculate a regression formula for future preoperative prediction of capsular bag diameter (CBDp).

SETTING: Department of Ophthalmology, University of Vienna, Austria.

METHODS: This prospective study comprised 70 eyes having cataract surgery with implantation of an open capsular tension ring (CTR) (Morcher Type 14). Within the first postoperative days, the distance between the ends of the CTR were measured through a gonioscopy lens by adjusting the slit height. This distance was added to the known length of the CTR to calculate the capsular bag circumference and from this, the CBDm. The CBDm was correlated with axial eye length (AL), corneal power (P), preoperative anterior chamber depth and lens thickness, corneal diameter, and age. A stepwise multiple regression analysis was computed with CBDm as the dependent variable.

RESULTS: The mean CBDm was 10.37 mm +/- 0.25 (SD). A statistically significant negative correlation was found between CBDm and P (P < .0004; r2 = 0.16) and a positive correlation between CBDm and AL (P < .0226, r2 = 0.07). Stepwise multiple regression resulted in the following regression formula: CBDp = 3.44 to 0.056 x P + 0.713 x AL - 0.0135 x AL2 (P < .0001; r2 = 0.3145). Using this formula with the individual Ps and ALs, all 6 eyes with a large capsular bag diameter (CBDm > 10.7 mm) and 10 of 13 eyes with a small one (CBDm < 10.1 mm) were correctly classified.

CONCLUSION: The capsular bag diameter in vivo correlated negatively with corneal power (P) and positively with AL. The regression formula used may serve as a tool for preoperative identification of eyes with a very large or very small CBDm.

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Prediction of residual astigmatism after cataract surgery using swept source fourier domain optical coherence tomography.

Curr. Eye Res., 2014; 1178-86

PURPOSE: To compare corneal measurements obtained by a swept source fourier domain OCT (CASIA SS-1000), an autokeratometer (Haag-Streit Lenstar), a hybrid topographer (Tomey TMS-5), a Placido topographer (Tomey TMS-5 in Placido mode) and a Scheimpflug tomographer (Oculus Pentacam) to manifest subjective refraction.

METHODS: One hundred and four pseudophacic patients with non-toric IOLs were measured at least 6 months after surgery. Corneal astigmatism as measured on the anterior corneal surface as well as total corneal astigmatism including posterior surface data was compared to manifest refractive cylinder (cross-cylinder strategy) by computing difference vectors and correlation analysis of power vectors.

RESULTS: The OCT (0.43 ± 0.25 D) and the hybrid topographer (0.44 ± 0.25 D) yielded the smallest difference vector to subjective cylinder and by far the lowest percentage of outliers >0.75 D (≈10%). The rotating Scheimpflug camera showed the largest (0.70 ± 0.41 D) difference vector. The best predictive precision (0.37 ± 0.22) could be achieved by vector averaging Lenstar keratometry and OCT.

CONCLUSIONS: Autokeratometry yielded the least measuring noise but OCT as well as hybrid topography had better predictive precision due to posterior curvature data. Scheimpflug tomography suffered from high measuring noise. Combination of keratometry and OCT data yielded the best precision for planning of toric IOL implantation. To get a reliable target cylinder for TIOL calculation, accuracy of the measuring device is crucial. Keratometry and Placido topography lack the information of the posterior corneal curvature while Scheimpflug devices suffer from higher measuring noise. In this paper, a combination of ssOCT with autokeratometry yielded the best predictive quality.

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Prediction of the true IOL position.

Br J Ophthalmol, 2017; 1440-1446

PURPOSE: To develop algorithms for preoperative estimation of the true postoperative intraocular lens (IOL) position to be used for IOL power calculation.

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, UK.

METHODS: Fifty patients were implanted randomly with a 3-piece IOL model in one eye and a 1-piece model in the other eye. Preoperatively, the IOLMaster was used to determine axial length, anterior chamber depth and mean corneal radius. Lens thickness and corneal width were measured with the ACMaster. Postoperative IOL position was measured with the ACMaster. Partial least squares (PLS) regression analysis of IOL position in terms of preoperative parameters was performed with a commercially available software package.

RESULTS: The PLS regression analysis showed that age, refraction, corneal width, lens thickness and corneal radius are not significant predictors of postoperative position of the anterior IOL surface, while axial length and in particular anterior chamber depth are. Regression relationships in terms of the above-mentioned predictors were determined for the two models implanted. Surprisingly, it turned out that the position of the posterior IOL surface could be described by a single regression relationship valid for both models. The residual SD for prediction of IOL position was about 0.17 mm for all relationships.

CONCLUSIONS: Accurate relationships to determine the true postoperative IOL position were obtained. In addition to axial length and corneal radius, which are required for the IOL power calculation as such, they require measurement of preoperative anterior chamber depth only.

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Prospective multicenter trial of a small-aperture intraocular lens in cataract surgery.

J Cataract Refract Surg, 2017; 956-968

PURPOSE: To evaluate the clinical acceptability of monocular implantation of the small-aperture (IC-8) intraocular lens (IOL) in 1 eye and an aspheric monofocal IOL in the fellow eye of bilateral cataract patients over 6 months postoperatively.

SETTING: Twelve clinics in Austria, Belgium, Germany, Italy, Spain, and Norway.

DESIGN: Prospective case series.

METHODS: The visual acuity, depth of focus, contrast sensitivity, patient satisfaction, visual symptoms, and adverse events were assessed in patients who had bilateral cataract surgery followed by implantation of the small-aperture IOL in 1 eye and an aspheric monofocal IOL in the fellow eye. Uncorrected distance (UDVA), intermediate (UIVA), and near (UNVA) visual acuities were reported in Snellen notation.

RESULTS: The study comprised 105 patients. At 6 months, the UDVA, UIVA, and UNVA in eyes with the small-aperture IOL were 20/23, 20/24, and 20/30, respectively. Ninety-nine percent, 95%, and 79% of patients achieved 20/32 or better binocular UDVA, UIVA, and UNVA, respectively. Ninety-three patients (95.9%) reported they would have the procedure again versus 4 patients (4.1%) who reported they would not have the procedure again. In eyes with the small-aperture IOL, the target-corrected defocus curve measured with 0.75 diopter (D) of myopia extended the range of functional near vision by an additional diopter without loss of distance vision compared with the distance-corrected defocus curves. The mean UIVA and UNVA remained at 20/25 and 20/32, respectively, for up to 1.5 D of residual astigmatism in eyes with the small-aperture IOL.

CONCLUSION: The small-aperture IOL showed excellent visual performance, safety, patient satisfaction, and tolerance to residual astigmatism 6 months after implantation.

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Pupil dilation dynamics with an intracameral fixed combination of mydriatics and anesthetic during cataract surgery.

J Cataract Refract Surg, 2018; 341-347

PURPOSE: To compare the pupil dynamics of an intracameral combination of 2 mydriatics and 1 anesthetic (Mydrane) to a standard topical regimen for cataract surgery.

SETTING: Sixty-two centers in Europe and 6 centers in Algeria.

DESIGN: Prospective case series.

METHODS: Pupil size measurements were performed in 2 randomized studies (phase 2 and phase 3) under masked conditions (recorded videography, masked reading center). The outcomes in the phase 2 study supported evaluation of the timeframe to obtain pupil dilation and the phase 3 study provided results on mydriasis stability.

RESULTS: Phase 2 and phase 3 comprised 139 patients and 591 patients, respectively. After intracameral combination administration, 95% of the pupil dilation was achieved within a mean of 28.6 seconds ± 4.6 (SD). At the beginning of capsulorhexis creation, the mean pupil diameter was larger than 7.0 mm in both groups. The intraoperative pupil diameter remained stable in the intracameral combination group and decreased in the topical group. The mean change in pupil size just before capsulorhexis to the end of surgery (just before cefuroxime injection) was -0.22 ± 0.72 mm and -1.67 ± 0.98 mm, respectively. No clinically significant change in pupil diameter (change <1.0 mm) occurred in the majority of the intracameral combination group (89.3%) compared with the topical group (26.8%).

CONCLUSIONS: Intracameral combination of 2 mydriatics and 1 anesthetic is an alternative to topical mydriatics for cataract surgery. The prompt onset of pupil dilation and the stable mydriasis induced by this drug combination improved the intraoperative conditions during crucial steps, such as intraocular lens implantation.

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Quality of vision after bilateral multifocal intraocular lens implantation: a randomized trial--AT LISA 809M versus AcrySof ReSTOR SN6AD1.

Ophthalmology, 2015; 700-10

PURPOSE: To compare postoperative visual symptoms and spectacle freedom after bilateral implantation of the AT LISA 809M (Carl Zeiss Meditec, Jena, Germany) versus the AcrySof ReSTOR SN6AD1 (Alcon Laboratories, Irvine, CA) multifocal intraocular lens (IOL).

DESIGN: Double-masked, prospective, randomized, controlled clinical trial.

PARTICIPANTS: A total of 188 patients undergoing bilateral sequential cataract surgery or bilateral refractive lens exchange.

METHODS: Patients were preoperatively randomized (allocation ratio 1:1) to bilateral implantation with the AT LISA 809M IOL or ReSTOR SN6AD1 IOL. Postoperative outcomes were assessed 4 to 8 months after second eye surgery.

MAIN OUTCOME MEASURES: The primary outcome was visual symptoms evaluated with the Quality of Vision (QoV) questionnaire. Secondary outcomes included other questionnaire data (CatQuest-9SF, spectacle independence, vision satisfaction, and dysphotopsia) and visual function measures (near, intermediate, and distance visual acuity, binocular reading speed [International Reading Speed Texts], contrast sensitivity, and forward light scatter). Adverse events, including intraoperative and postoperative complications, also were evaluated.

RESULTS: There was no significant difference between IOL groups in Rasch-adjusted QoV scores for frequency (P = 0.95), severity (P = 0.56), and bothersomeness (P = 0.34) of visual symptoms; median (interquartile) scores for these QoV subscales were 29 (15-37), 22 (13-27), and 14 (0-29) for the AT LISA 809M IOL group, respectively, and 32 (15-37), 22 (13-30), and 14 (0-29) for the ReSTOR SN6AD1 IOL group, respectively. Halo was the most prominent dysphotopsia symptom, with 6% in both IOL groups reporting halo symptoms as very bothersome. Complete spectacle independence was achieved in 69 of 84 (82.1%) AT LISA 809M recipients and 66 of 85 (77.6%) ReSTOR SN6AD1 recipients (P = 0.57). Preferred reading distance was slightly nearer for the AT LISA 809M IOL. There were no statistically significant differences in any of the other secondary outcome measures.

CONCLUSIONS: Visual symptoms were similar after bilateral implantation of the AT LISA 809M and ReSTOR SN6AD1 IOLs. Both these diffractive bifocal IOLs produce high levels of spectacle independence and patient satisfaction. However, a small but clinically significant minority of patients remained symptomatic and dissatisfied with visual results 4 to 8 months after surgery.

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Randomised fellow eye comparison of the effectiveness of dorzolamide and apraclonidine on intraocular pressure following phacoemulsification cataract surgery.

Eye (Lond), 2000; 757-60

PURPOSE: To compare the effectiveness of 2% dorzolamide and 0.5% apraclonidine on intraocular pressure (IOP) following phacoemulsification cataract surgery.

METHODS: This prospective, randomised study comprised 54 eyes of 27 consecutive patients with age-related cataract scheduled for cataract surgery in both eyes. In each patient the eye with the higher degree of cataract was randomly assigned to receive one drop of either dorzolamide or apraclonidine immediately after surgery. The fellow eye was operated on later and received the other treatment. Cataract surgery was performed with a superior 6.0 mm sutureless frown incision, phacoemulsification and implantation of a three-piece PMMA intraocular lens. The IOP was measured pre-operatively as well as 6 h and 20-24 h and 1 week post-operatively.

RESULTS: The mean pre-operative IOP was not significantly different between the groups (dorzolamide group, 14.9 +/- 2.3 mmHg; apraclonidine group, 14.6 +/- 2.5 mmHg; p = 0.450). At 6 h post-operatively, the mean IOP was significantly lower in the dorzolamide than in the apraclonidine group (15.6 +/- 3.9 mmHg vs 18.0 +/- 4.0 mmHg; p < 0.001). An IOP increase of more than 5 mmHg at 6 h post-operatively occurred in 3 (12%) eyes in the dorzolamide group and in 9 (36%) eyes in the apraclonidine group (p = 0.034). At 20-24 h post-operatively and at 1 week post-operatively no difference was found between the groups.

CONCLUSIONS: 2% Dorzolamide is more effective than 0.5% apraclonidine in preventing the early post-operative IOP increase following phacoemulsification cataract surgery.

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Randomized trial of multifocal intraocular lenses versus monovision after bilateral cataract surgery.

Ophthalmology, 2013; 2449-2455.e1

OBJECTIVE: To compare spectacle independence in patients randomized to receive bilateral multifocal intraocular lenses (IOLs) or monofocal IOLs with the powers adjusted to produce monovision.

DESIGN: Randomized, multicenter clinical trial.

PARTICIPANTS: A total of 212 patients with bilateral, visually significant cataract.

METHODS: Before bilateral sequential cataract surgery, patients were randomized (allocation ratio 1:1) to receive bilateral Tecnis ZM900 diffractive multifocal lenses (Abbott Medical Optics, Santa Ana, CA) or Akreos AO monofocal lenses (Bausch & Lomb, Rochester, NY) with the powers adjusted to target -1.25 diopters (D) monovision. Outcomes were assessed 4 months after the second eye underwent operation.

MAIN OUTCOME MEASURES: The primary outcome was spectacle independence. Secondary outcomes included questionnaires (VF-11R, dysphotopsia symptoms, and satisfaction) and visual function measures (near, intermediate, and distance logarithm of minimum angle of resolution [logMAR] visual acuity, stereoacuity, contrast sensitivity, and forward light scatter).

RESULTS: A total of 212 patients were randomized, and 187 patients (88%) returned for assessment 4 months after surgery. Uniocular distance refractions in the monovision arm showed a mean spherical equivalent of +0.075 D in the distance eye and -0.923 in the near eye. In the multifocal arm, the mean distance spherical equivalents were -0.279 D and -0.174 D in the right and left eyes, respectively. A total of 24 of 93 patients (25.8%) in the monovision arm and 67 of 94 patients (71.3%) in the multifocal arm reported never wearing glasses (P<0.001, Fisher exact test). The adjusted odds ratio of being spectacle free was 7.51 (95% confidence interval, 3.89-14.47). Binocular uncorrected acuities did not differ significantly for distance (0.058 logMAR for monovision vs. 0.076 for multifocal, P = 0.3774) but were significantly worse in the multifocal arm for intermediate acuity (0.149 vs. 0.221, P = 0.0001) and in the monovision arm for near acuity (0.013 vs. -0.025, P = 0.037). In the first postoperative year, 6 patients (5.7%) in the multifocal arm underwent IOL exchange (4 had a bilateral and 2 had a unilateral exchange). No patients in the monovision arm underwent IOL exchange.

CONCLUSIONS: Patients randomized to bilateral implantation with the diffractive multifocal Tecnis ZM900 were more likely to report being spectacle independent but also more likely to undergo IOL exchange than those randomized to receive monofocal implants (Akreos AO) with the powers adjusted to give low monovision.

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Ray tracing for intraocular lens calculation.

J Cataract Refract Surg, 2002; 1412-9

PURPOSE: To improve accuracy in intraocular lens (IOL) calculations and clarify the effect of various errors.

SETTING: University eye hospitals, Mainz, Germany, and Vienna, Austria.

METHODS: A numerical ray-tracing calculation has been developed for the pseudophakic eye. Individual rays are calculated and then undergo refractions on all surfaces of the IOL and cornea. The calculations do not use approximations; ie, the refractions are calculated exactly using Snell's law. Rays can be calculated for any distance from the optical axis and for other parameter variations. The effects of aspheric surfaces can also be investigated. Instead of IOL powers, manufacturers' IOL data (radii, refractive index, thickness) are used in the calculations for different IOL types. The resulting optical quality is visualized by using Landolt rings superimposed on the grid of retinal receptors.

RESULTS: Intraocular lens design, corneal asphericity, and specific spherical aberration influence the visual quality of the pseudophakic eye significantly. The IOL refractive power is an ambiguous parameter that cannot characterize the visual outcome sufficiently accurately for an IOL implanted at a given position. The effects can be calculated only in numerical ray tracing, not in Gaussian optics. The accuracy of numerical ray tracing is independent of axial length. Therefore, very long or very short eyes gain the most from the higher accuracy of this approach. For average-size eyes, however, the results are the same as with SRK calculations.

CONCLUSION: Calculations in Gaussian optics should be replaced by state-of-the-art numerical methods, which can be run on any standard personal computer.

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Refractive outcome of cataract surgery using partial coherence interferometry and ultrasound biometry: clinical feasibility study of a commercial prototype II.

J Cataract Refract Surg, 2002; 230-4

PURPOSE: To evaluate the refractive outcome of cataract patients 3 months postoperatively using optical biometry obtained with a prototype version (axial length measurement, ALM, Carl Zeiss Jena) of the commercial partial coherence interferometry (PCI) instrument (IOLMaster, Carl Zeiss Jena).

SETTING: Department of Ophthalmology, Vienna General Hospital, and Institute of Medical Physics, University of Vienna, Austria.

METHODS: Forty-five patients with age-related cataract in both eyes were scheduled for bilateral cataract surgery. Axial length was measured preoperatively with a prototype (ALM) of the commercial PCI instrument as well as with immersion ultrasound (IUS). Immersion US was performed by a single experienced investigator. In each patient, the first eye was randomly assigned to receive an intraocular lens (IOL) using the Holladay IOL power formula based on ALM or IUS biometry. The other biometric technique was used in the contralateral eye. Subjective refractive outcome was assessed 3 months postoperatively.

RESULTS: Refractive outcomes with the 2 techniques did not differ significantly (P = .28). The mean numerical error (MNE) (the difference between the refractive outcome 3 months postoperatively and the predicted spherical equivalent) was 0.13 diopter (D) and 0.03 D for the ALM and IUS, respectively. The mean absolute error (MAE) (the absolute value of MNE) was 0.48 D (range 0.00 to 1.58 D) and 0.46 D (range 0.01 to 1.92 D) with the ALM and IUS, respectively. By recalculating the surgeon factor retrospectively to correct the Holladay formula to obtain a postoperative MNE of zero, a theoretical MAE of 0.46 D was obtained with both biometry techniques.

CONCLUSIONS: Refractive outcome in cataract patients using PCI biometry was as good as that achieved with optimized IUS. However, the difference in axial length measured by the ALM compared to that measured by IUS must be considered when using the IOL A-constants supplied by the manufacturers.

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Reliability and reproducibility of the German version of the European Society of Cataract and Refractive Surgeons reading charts.

J Cataract Refract Surg, 2015; 1465-9

PURPOSE: To create a validated, standardized, logarithmic European Society of Cataract and Refractive Surgeons (ESCRS) reading chart in German and to use this reading chart as a template for comparable reading charts in other languages.

SETTING: Hanusch Hospital, Vienna, and Department of Ophthalmology, Paracelsus Medical University, Salzburg, Austria.

DESIGN: Prospective multicenter validation study.

METHODS: Thirty-nine short standardized German sentences were developed and tested on healthy volunteers and pseudophakic patients. On the first visit, corrected distance visual acuity was assessed in each eye using autorefraction (KR8000) and subjective refraction using Early Treatment Diabetic Retinopathy Study charts at 4 m. Reading speed, when reading the new ESCRS reading charts, was tested under photopic conditions (85 to 100 candelas/m(2)) and high contrast (≥95% Michelson contrast).

RESULTS: The study assessed 120 subjects. Sixty subjects were young healthy volunteers and 60 were pseudophakic patients. Reliability of the sentences was tested using Cronbach's α and was found to be high (α = 0.994). Furthermore, reproducibility was high in most cases and the absolute mean difference between the first measurement and second measurement for all sentences was 0.56 seconds ± 0.07 (SD) (range 0.43 to 0.72 seconds).

CONCLUSION: The German version of the ESCRS reading charts, a standardized logarithmic and validated reading test, was reliable in healthy volunteers as well as in pseudophakic patients.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

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Reliability of a video-based noncontact specular microscope for assessing the corneal endothelium.

Cornea, 2007; 924-9

PURPOSE: To assess the within- and between-examiner reliability of corneal endothelial cell density (ECD) measurements with 2 noncontact specular microscopes: a video-based system (SeaEagle) and a photographic system (Noncon Robo).

METHODS: In 57 eyes of 57 subjects, 47 healthy subjects and 10 patients with corneal disease, ECD was measured in the center and at 4 paracentral areas with the video-based system (SeaEagle) and in the center with a photographic system (Noncon Robo). For the between-examiner reliability, a second examiner measured the central ECD with the SeaEagle device in 12 healthy subjects. The video-based system was also used to evaluate the agreement between the automated and the manually corrected (semiautomated) modes of repeated measurements.

RESULTS: For central ECD in all eyes, the test-retest reliability assessed by the intraclass correlation coefficient was 0.77, 0.99, and 0.91 for the automated SeaEagle, semiautomated SeaEagle, and Noncon Robo, respectively. Correlation was poor to good between the 3 measurement methods (range, 0.61-0.84). For between-examiner reliability, the upper (lower) limits of agreement were 200 (-384) and 149 (-92) cell/mm for the automated and semiautomated SeaEagle, respectively.

CONCLUSIONS: The best reliability of repeated measurements was found for the semiautomated SeaEagle. However, the semiautomated method showed significantly higher ECD values than the Noncon Robo, and this difference was highly dependent on ECD. Thus, we suggest that these methods should not be used interchangeably. The fully automated mode may need a further refinement of the cell detection algorithm.

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Removal of reflections in the photographic assessment of PCO by fusion of digital retroillumination images.

Invest. Ophthalmol. Vis. Sci., 2003; 275-80

PURPOSE: Automated image-analysis systems for objective assessment of posterior capsule opacification (PCO) depend on good image quality. One major drawback is the existence of light-reflection artifacts (Purkinje spots) in retroillumination images of the posterior capsule. Therefore, a software algorithm was developed that removes these artifacts by fusion of two or more digital images from the same eye, photographed in slightly different directions of gaze.

METHODS: The image-fusion process comprises five steps: definition of a primary and a secondary image, automated segmentation of the region of interest and the Purkinje spots, manual selection of three pairs of corresponding points in both images, geometric registration and radiometric calibration of the regions to be inserted from the secondary image into the primary image. The program was tested with an image set of 30 eyes that had various degrees of PCO. A digital image acquisition system with a coaxial optical path was used to take retroillumination images from each eye in at least three different directions of gaze.

RESULTS: In 28 cases all light-reflection artifacts within the capsulorrhexis rim could be removed entirely. In two cases, small parts of single Purkinje spots remained visible, because the reflections were located too closely in the primary and the secondary images.

CONCLUSIONS: Fusion of digital retroillumination images provides high-quality, reflection-free PCO images. This allows objective PCO assessment systems to analyze 100% of the posterior capsule, leading to more accurate results.

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Renal and ocular hemodynamic effects of insulin.

Diabetes, 1997; 1868-74

There is evidence that the vasodilator action of insulin is mediated by the release of nitric oxide (NO). We hypothesized that euglycemic hyperinsulinemia might increase renal and ocular blood flow, and that the vasodilator capacity of insulin might be NO-dependent. Euglycemic insulin clamps were performed in 10 healthy subjects. Sixty minutes after the start of insulin administration, an intravenous coinfusion of N-monomethyl-L-arginine (L-NMMA), an inhibitor of NO synthase, or of norepinephrine (NE), an endothelium-independent vasoconstrictor, was started. Renal plasma flow was measured by para-aminohippurate (PAH) clearance method. Ocular hemodynamics were assessed by laser interferometric measurement of fundus pulsations and Doppler sonographic measurement of blood flow velocity in the ophthalmic artery. Renal plasma flow and ocular fundus pulsations were increased by insulin. L-NMMA almost completely abolished the vasodilative effects of insulin, whereas the effects of combined infusion of insulin and NE were approximately the sum of the hemodynamic changes induced by each agent alone. The results show that during euglycemic hyperinsulinemia, renal and ocular blood flow are increased, which may be mediated either by a local vasodilator effect or a systemic increase in flow. The hemodynamic effects of insulin in the kidney and the eye are at least partially dependent on NO synthesis. Because the insulin plasma levels we obtained are in the high physiological range, it may be assumed that insulin plays a role in renal and ocular blood flow regulation.

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Reply.

J Cataract Refract Surg, 2016; 1545

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Reply: a simple technique for corneal marking before toric intraocular lens implantation.

J Cataract Refract Surg, 2013; 967-8

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Reproducibility and sensitivity of scanning laser Doppler flowmetry during graded changes in PO2.

Br J Ophthalmol, 1997; 360-4

AIMS/BACKGROUND: Recently a commercially available scanning laser Doppler flowmeter has been produced, which provides two dimensional maps of the retinal perfusion. The aim of the present study was to investigate the reproducibility and the sensitivity of these measurements.

METHODS: 16 healthy subjects were randomised to inhale different gas mixtures of oxygen and nitrogen in a double blind crossover study. The following gas mixtures of oxygen and nitrogen were administered: 100% oxygen + 0% nitrogen, 80% oxygen + 20% nitrogen, 60% oxygen + 40% nitrogen, 40% oxygen + 60% nitrogen, 30% oxygen + 70% nitrogen, 20% oxygen + 80% nitrogen, 15% oxygen + 85% nitrogen, and 10% oxygen + 90% nitrogen. Retinal haemodynamic variables and systemic haemodynamics were measured during all inhalation periods. Recordings under resting conditions were performed three times to calculate intraclass coefficients.

RESULTS: In two subjects we did not obtain technically adequate results. A dose dependent change in retinal blood flow during graded oxygen breathing was observed (p < 0.001). During 100% oxygen breathing blood flow decrease was between 29% and 33%, whereas blood flow increase was between 28% and 33% during inhalation of 10% oxygen + 90% nitrogen.

CONCLUSIONS: Scanning laser Doppler flowmetry has an acceptable reproducibility and is appropriate for description of the effect of graded changes in PO2 on retinal haemodynamics. The main problems with the system are the large zero offset, the fixation during retinal scanning, and the neglect of blood flow changes during the cardiac cycle.

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Reproducibility of an analysis software for qualitative observation of Elschnig pearls.

Ophthalmic Surg Lasers Imaging, ; 507-11

BACKGROUND AND OBJECTIVE: To determine the reproducibility of a semi-objective analysis software for the morphological analysis of single Elschnig pearls from retroillumination images of posterior capsule opacification.

PATIENTS AND METHODS: In this prospective study, images of eyes with varying degrees of regeneratory posterior capsule opacification and the presence of Elschnig pearls were taken. The size and morphology of single Elschnig pearls was evaluated from consecutive images using an analysis method called PearlTracer using three different modes: snake selection, where a few points detected the pearl border automatically; diameter circle selection, a circle function; and polygon selection, where several points were connected by straight lines. The interobserver and intraobserver reproducibility and the limits of the different modes concerning contrast were assessed.

RESULTS: One hundred fifty-eight retroillumination images of 55 eyes of 50 patients were included with a total of 857 pearls being analyzed. A high interobserver reproducibility was found, as well as a high intraobserver reproducibility. Furthermore, a significant difference in the pearl size and the pearl morphology between the three analysis features of the software was found.

CONCLUSION: For the observation of single Elschnig pearls and their morphological changes, the semi-objective PearlTracer analysis software was found to be a highly reproducible and useful method.

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Reproducibility of intraocular lens decentration and tilt measurement using a clinical Purkinje meter.

J Cataract Refract Surg, 2010; 1529-35

PURPOSE: To determine the reproducibility of intraocular lens (IOL) decentration and tilt measurements with a new Purkinje meter instrument.

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

METHODS: After pupil dilation, images of pseudophakic eyes with a plate-style IOL (Akreos Adapt) were obtained using a recently developed Purkinje meter. Intraocular lens decentration and tilt were evaluated by analyzing the captured images using a semiobjective method by marking the reflexes in the images and automatic calculation using a dedicated software program. In study 1, examiner 1 examined the eyes first followed by examiner 2. Ten minutes later, examiner 1 performed a second measurement, after which the intraexaminer and interexaminer reproducibility were determined. In study 2, a Purkinje meter was used to measure pseudophakic eyes with slitlamp finding of clinical IOL decentration, IOL tilt, or both. The results were compared with retroillumination photographs and slitlamp findings.

RESULTS: In study 1, there was high intraexaminer reproducibility for decentration (r = 0.95) and tilt (r = 0.85) and high interexaminer reproducibility for decentration (r = 0.84) and tilt (r = 0.75). In study 2, even in extreme cases of decentration and/or tilt, the Purkinje meter measurements were possible and appeared to correlate well with slitlamp findings.

CONCLUSIONS: Acquisition of images in pseudophakic eyes with the Purkinje meter was simple and rapid. The method was highly reliable for 1 examiner and between 2 examiners.

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Reproducibility of standardized retroillumination photography for quantification of posterior capsule opacification.

J Cataract Refract Surg, 2002; 265-70

PURPOSE: To determine the short-term reproducibility of standardized digital retroillumination images of regeneratory posterior capsule opacification (PCO) using the photographic setup at 1 institution.

SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS: In this prospective study, 60 retroillumination images of 30 eyes with varying degrees of PCO and different types of intraocular lenses were acquired with a standardized digital coaxial retroillumination system. Two images were taken per eye with a 1-minute interval between images. Ten other eyes were photographed in the same way but with a 5-day interval between the 2 images. All images were evaluated with a fully automated, objective PCO analysis software in which the PCO score was from 0 to 100. The 2 results (A, B) in each eye were compared, and the differences were calculated.

RESULTS: There was a high correlation between the A and B results (r = 0.99). The mean absolute difference was 3.7%. The repeatability coefficient was 8.8%.

CONCLUSION: Digital coaxial retroillumination photography provided quick acquisition of regeneratory PCO images. It provided excellent image quality and high reproducibility. The technique forms a good basis for automated quantification of PCO with new software systems.

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Retinal blood flow during hyperoxia in humans revisited: concerted results using different measurement techniques.

Microvasc. Res., 2002; 75-85

Retinal vasculature shows pronounced vasoconstriction in response to hyperoxia, which appears to be related to the constant oxygen demand of the retina. However, the exact amount of blood flow reduction and the exact time course of this phenomenon are still a matter of debate. We set out to investigate the retinal response to hyperoxia using innovative techniques for the assessment of retinal hemodynamics. In a total of 48 healthy volunteers we studied the effect of 100% O(2) breathing on retinal blood flow using two methods. Red blood cell movement in larger retinal veins was quantified with combined laser Doppler velocimetry and retinal vessel size measurement. Retinal white blood cell movement was quantified with the blue field entoptic technique. The time course of retinal vasoconstriction in response to hyperoxia was assessed by continuous vessel size determination using the Zeiss retinal vessel analyzer. The response to hyperoxia as measured with combined laser Doppler velocimetry and vessel size measurement was almost twice as high as that observed with the blue field technique. Vasoconstriction in response to 100% O(2) breathing occurred within the first 5 min and no counterregulatory or adaptive mechanisms were observed. Based on these results we hypothesize that hyperoxia-induced vasoconstriction differentially affects red and white blood cell movement in the human retina. This hypothesis is based on the complex interactions between red and white blood cells in microcirculation, which have been described in detail for other vascular beds.

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Reversal of endothelin-1-induced ocular hemodynamic effects by low-dose nifedipine in humans.

Clin. Pharmacol. Ther., 1998; 54-63

BACKGROUND AND PURPOSE: There is evidence that calcium channel blockers may be useful in patients with normal tension glaucoma and vasospastic reactions. We therefore hypothesized that calcium channel blockers may increase ocular blood flow and that there may be a functional antagonism between endothelin-1 (ET-1) and calcium channel blockers in the ocular vasculature.

METHODS: This was a randomized, double-blind, three-way crossover study with respect to ET-1 infusions (placebo, 2 ng/kg/min ET-1, and 4 ng/kg/min ET-1) and a randomized double-blind study in two parallel groups with respect to nifedipine (placebo or 5 mg nifedipine). Ocular hemodynamics in the 12 healthy subjects participating in the study was assessed by laser interferometric measurement of fundus pulsation amplitude (FPA) in the optic disc and two-dimensional scanning laser Doppler flowmetry in the optic disc.

RESULTS: ET-1 caused a dose-dependent decrease in FPA and flow. With a dose of 4 ng/kg/min a decrease of -18% +/- 5% (p < 0.001) and -17% +/- 5% (p = 0.023) on FPA and flow, respectively, were observed. This effect was completely reversed by nifedipine compared with placebo (FPA, p < 0.001; flow, p = 0.011). However, nifedipine did not affect ocular hemodynamics after placebo infusion.

CONCLUSIONS: These results show that nifedipine does not increase optic nerve head blood flow during baseline conditions but reverses ET-1-induced constriction in ocular vasculature at doses that do not affect systemic hemodynamics. This supports the close relation of the therapeutic effect of calcium channel blockers in patients with normal tension glaucoma to the endothelin system. Moreover, the present study provides a strong rationale for a study of low dose nifedipine as a supplementary medication in glaucoma patients.

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Risk factors for postoperative intraretinal cystoid changes after peeling of idiopathic epiretinal membranes among patients randomized for balanced salt solution and air-tamponade.

Acta Ophthalmol, 2018;

PURPOSE: Epiretinal membranes (ERM) are macular disorders leading to loss of vision and metamorphopsia. Vitrectomy with membrane peeling displays the gold standard of care. Aim of this study was to assess risk factors for postoperative intraretinal cystoid changes in a study population randomized for balanced salt solution and air-tamponade at the end of surgery.

METHODS: A prospective randomized study, including 69 eyes with idiopathic ERM. Standard 23-gauge three-port pars plana vitrectomy with membrane peeling, using intraoperative optical coherence tomography (OCT), was performed. Randomization for BSS and air-tamponade was performed prior to surgery.

RESULTS: Best-corrected visual acuity improved from 32.9 letters to 45.1 letters 3 months after surgery. Presence of preoperative intraretinal cystoid changes was found to be the only risk factor for presence of postoperative intraretinal cystoid changes 3 months after surgery (p = 0.01; odds ratio: 8.0). Other possible risk factors such as combined phacoemulsification with 23G-ppv and membrane peeling (p = 0.16; odds ratio: 2.4), intraoperative subfoveal hyporeflective zones (p = 0.23; odds ratio: 2.6), age over 70 years (p = 0.29; odds ratio: 0.5) and air-tamponade (p = 0.59; odds ratio: 1.5) were not found to be significant.

CONCLUSION: There is strong evidence that preoperative intraretinal cystoid changes lead to smaller benefit from surgery.

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Role of NO in the O2 and CO2 responsiveness of cerebral and ocular circulation in humans.

Am. J. Physiol., 1997; R2005-12

It is well known that changes in PCO2 or PO2 strongly influence cerebral and ocular blood flow. However, the mediators of these changes have not yet been completely identified. There is evidence from animal studies that NO may play a role in hypercapnia-induced vasodilation and that NO synthase inhibition modulates the response to hyperoxia in the choroid. Hence we have studied the effect of NO synthase inhibition by NG-monomethyl-L-arginine (L-NMMA, 3 mg/kg over 5 min as a bolus followed by a continuous infusion of 30 micrograms.kg-1.min-1) on the changes of cerebral and ocular hemodynamic parameters elicited by hypercapnia and hyperoxia in healthy young subjects. Mean flow velocities in the middle cerebral artery and the ophthalmic artery were measured with Doppler ultrasound, and ocular fundus pulsation amplitude, which estimates pulsatile choroidal blood flow, was measured with laser interferometry Administration of L-NMMA reduced ocular fundus pulsation. (-19%, P < 0.005) but only slightly reduced mean flow velocities in the larger arteries. Hypercapnia (PCO2 = 48 mmHg) significantly increased mean flow velocities in the middle cerebral artery (+26%, P < 0.01) and fundus pulsation amplitude (+16%, P < 0.005) but did not change mean flow velocity in the ophthalmic artery. The response to hypercapnia in the middle cerebral artery (P < 0.05) and in the choroid (P < 0.05) was significantly blunted by L-NMMA. On the contrary, L-NMMA did not affect hyperoxia-induced (PO2 = 530 mmHg) hemodynamic changes. The hemodynamic effects of L-NMMA (at baseline and during hypercapnia) were reversed by coadministration of L-arginine. The present study supports the concept that NO has a role in hypercapnia induced vasodilation in humans.

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Rotational performance and corneal astigmatism correction during cataract surgery: aspheric toric intraocular lens versus aspheric nontoric intraocular lens with opposite clear corneal incision.

J Cataract Refract Surg, 2014; 1355-62

PURPOSE: To compare the astigmatism-reducing effect of an aspheric toric intraocular lens (IOL) and an aspheric nontoric IOL with an opposite clear corneal incision (OCCI) in cataract surgery.

SETTING: Vienna Institute for Research in Ocular Surgery, Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective randomized clinical study.

METHODS: Patients with low to moderate corneal astigmatism scheduled for cataract surgery received an aspheric toric IOL (Lentis L-312T) or an aspheric nontoric IOL (Lentis L-312) combined with an OCCI. Keratometry and corneal tomography were performed 1 hour, 1 week, 3 months and 9 months postoperatively. Postoperative residual astigmatism was measured using an autorefractor. Rotational toric IOL stability was analyzed using retroillumination photography.

RESULTS: Fifty-five patients were included. Three months postoperatively, the mean reduction in corneal astigmatism was 0.67 diopter (D) ± 0.58 (SD) in the toric group and 0.18 ± 0.52 D in the nontoric-OCCI group. The mean uncorrected distance visual acuity was 0.29 ± 0.30 logMAR and 0.09 ± 0.18 logMAR, respectively (P=.02). The mean refractive astigmatism was 1.02 ± 0.54 D and 0.68 ± 0.52 D, respectively (P=.05). One hour, 3 months, and 9 months postoperatively, the mean absolute IOL misalignment of toric IOLs was 4.99 ± 4.66 degrees, 13.59 ± 11.29 degrees, and 19.90 ± 14.48 degrees, respectively.

CONCLUSIONS: The toric IOL tended to rotate significantly postoperatively. Visual acuity was good in both groups. Residual refractive cylinder was significantly lower in the toric IOL group.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

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Rotational stability and posterior capsule opacification of a plate-haptic and an open-loop-haptic intraocular lens.

J Cataract Refract Surg, 2011; 251-7

PURPOSE: To compare the rotational stability and posterior capsule opacification (PCO) rate in eyes with a 1-piece or 3-piece acrylic intraocular lens (IOL).

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

DESIGN: Prospective randomized masked clinical trial.

METHODS: Patients with age-related cataract received a plate-haptic acrylic IOL (Acri.Smart 46S) in 1 eye and a 3-piece loop-haptic acrylic IOL (Acri.Lyc 53N) in the other eye. Retroillumination images were taken 1 hour, 1 week, and 1, 6, and 12 months postoperatively. Intraocular lens rotation was measured using standard software (Adobe Photoshop). The amount of PCO was assessed subjectively at the slitlamp and objectively using an automated image-analysis software (AQUA).

RESULTS: The study enrolled 80 eyes of 40 patients. The IOL rotation measurements showed excellent reproducibility, with a deviation of less than 0.8 degrees. Both IOLs had comparable and good rotational stability; rotation was less than 4 degrees in 71% of eyes 1 year postoperatively. The mean absolute rotation was 2.6 degrees ± 1.9 (SD) in the plate-haptic IOL group and 3.1 ± 2.4 degrees in the loop-haptic IOL group. The mean AQUA PCO score (scale 0 to 10) was 0.4 in both IOL groups (P = .7).

CONCLUSION: The 2 IOL models had comparable, excellent rotational stability and low PCO intensity 1 year postoperatively. Thus, the plate-haptic IOL may be a good platform for a toric model.

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Rotational stability of 2 intraocular lenses with an identical design and different materials.

J Cataract Refract Surg, 2017; 234-238

PURPOSE: To evaluate the rotational stability of nontoric intraocular lenses (IOLs) of the same design and different materials.

SETTING: Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective randomized case series.

METHODS: This study included cataract patients with a corneal astigmatism of less than 1.75 diopters measured with the IOLMaster 500. Each patient received a hydrophilic IOL (Pod Ay 26P) in 1 eye and a hydrophobic IOL (Podeye) in the other eye. One hour and 3 months postoperatively, retroillumination photographs were taken to assess rotational stability of the IOLs. In addition, autorefraction, subjective refraction, and Purkinje meter measurements were performed at the 3-month follow-up.

RESULTS: Eighty eyes of 40 patients were included in this study. Three months postoperatively, the IOL rotation within the first 3 months was 2.4 degrees ± 1.85 (SD) in the hydrophilic IOL group and 1.6 ± 1.61 degrees in the hydrophobic IOL group. This difference was statistically significant (P = .016).

CONCLUSION: The hydrophobic IOL was rotationally more stable than the hydrophilic IOL, although both IOLs provided good capsular bag stability.

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Rotational stability of a single-piece toric acrylic intraocular lens.

J Cataract Refract Surg, 2010; 1665-70

PURPOSE: To assess the rotational stability of a single-piece toric hydrophobic acrylic intraocular lens (IOL) during the first 6 postoperative months.

SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.

DESIGN: Prospective case series.

METHOD: Eyes with age-related cataract and corneal astigmatism (1.00 to 3.00 D diopter [D]) were measured by partial coherence interferometry (IOLMaster). Preoperatively, the horizontal axis was marked. Surgical technique included a standardized temporal clear corneal incision, phacoemulsification, and in-the-bag implantation of a toric IOL (AcrySof SN60TT). Rotational stability of the IOL was assessed using retroillumination photographs postoperatively at 1 hour and at 1 and 6 months. Uncorrected (UDVA) and corrected distance visual acuities, residual refractive error, and keratometric and refractive cylinders were measured.

RESULTS: The study enrolled 30 eyes (30 patients). The mean absolute IOL rotation was 2.44 degrees ± 1.84 (SD) at 1 month and 2.66 ± 1.99 degrees at 6 months. The photographic technique had high reproducibility of axis measurement, with consecutive measurements varying by less than 2.0 degrees. The mean UDVA was 0.16 logMAR (range 0.42 to -0.18 logMAR) at 1 month and 0.20 logMAR (range 0.60 to -0.20 logMAR) at 6 months. The residual refractive cylinder by autorefraction was -0.84 D (range -2.00 to 0.00 D) and -0.80 D (range -1.75 to 0.00 D), respectively.

CONCLUSIONS: The acrylic toric IOL was rotationally stable within the first 6 months postoperatively. The photographic and axis analysis method to evaluate stability had high reproducibility and detected small changes in rotation.

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Rotational stability of a single-piece toric acrylic intraocular lens: a pilot study.

Am. J. Ophthalmol., 2014; 405-411.e1

PURPOSE: To evaluate the visual performance and rotational stability of the Tecnis Toric 1-piece intraocular lens (IOL) during the first 3 postoperative months.

DESIGN: Prospective, single-center study.

METHODS: In this study, patients with age-related cataract and corneal astigmatism of 1.0 to 3.0 diopters measured with the IOLMaster 500 (Carl Zeiss Meditec AG) were included. Before surgery, rotating Scheimpflug scans (Pentacam HR; Oculus) were performed and the cornea was marked in the sitting position at the slit lamp. Patients received a single-piece toric hydrophobic acrylic IOL (Tecnis Toric; AMO). Immediately and 3 months after surgery, retroillumination photographs were obtained to assess the rotational stability of the IOL. Additionally, Autorefraction (Topcon), subjective refraction, uncorrected and distance-corrected visual acuity, keratometry, and Scheimpflug and ocular wavefront (WASCA, Carl Zeiss Meditec AG) measurements were performed at the 3-month follow-up.

RESULTS: Thirty eyes of 30 patients were included in this study. Mean absolute difference between the IOL axis at the 3-month and 1-hour follow-up was 2.7 degrees (standard deviation, 3.0 degrees). The IOL rotation was less than 3 degrees and less than 6 degrees in 62% and 95% of all cases, respectively.

CONCLUSIONS: The Tecnis Toric 1-piece IOL is rotationally stable and shows excellent capsule bag performance and refractive outcomes.

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Short-term changes in the morphology of posterior capsule opacification.

J Cataract Refract Surg, 2005; 962-8

PURPOSE: To observe and document posterior capsule opacification (PCO) growth in vivo over a short period of time (4 weeks).

SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS: Fifteen eyes of pseudophakic patients with PCO of varying degrees were included in this prospective study. Digital retroillumination images were taken in a standardized fashion at 3 time points: 1 baseline image, a second image after 2 weeks, and a third image after 4 weeks. Thus, a 3-image series could be created for each eye. Additionally, sections of the posterior capsule with interesting structures were photographed with higher magnification and compared in supplementary image series. Morphologic changes in the PCO structure (eg, number and size of Elschnig pearls, total PCO area) were analyzed in the image series.

RESULTS: In all cases, significant changes could be observed between the 3 time points. In 71% of cases, some Elschnig pearls increased in size during the first 2 weeks and during weeks 3 and 4. In 73% of cases, however, there was a reduction a pearl size or even disappearance of some Elschnig pearls. The total PCO area did not change significantly during the 4-week period.

CONCLUSIONS: Development of (regeneratory) PCO is a very dynamic process that includes not only growth of preexisting structures and occurrence of new Elschnig pearls, but also reorganization and even disappearance of pearls within a short time period (2-4 weeks). The latter in particular is not well known but could be observed in the majority of cases in this study.

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Short-term effect of dorzolamide hydrochloride on central corneal thickness in humans with cornea guttata.

Arch. Ophthalmol., 2003; 621-5

OBJECTIVE: To investigate the short-term effect of dorzolamide hydrochloride, a topical carbonic anhydrase inhibitor, on central corneal thickness in patients with cornea guttata.

DESIGN AND METHODS: In this randomized, placebo-controlled, double-masked, 3-drug crossover study, 20 patients with cornea guttata (mean endothelial cell count, 1321 cells/mm2) and 8 healthy control subjects (mean endothelial cell count, 2483 cells/mm2) were included. Study medications included 2% dorzolamide hydrochloride (Trusopt 2% eye drops; Merck & Co Inc, Whitehouse Station, NJ), 0.9% saline solution (saline placebo), and a solution identical to the carrier substance of dorzolamide in Trusopt (carrier placebo). The study drugs were applied 4 times per day for 1 day only. Central corneal thickness measurements were performed using partial coherence interferometry on every study day at baseline and after 24 hours of study medication treatment.

MAIN OUTCOME MEASURES: Change in central corneal thickness.

RESULTS: The mean thickening in central corneal thickness within 24 hours in eyes with cornea guttata treated with dorzolamide, saline placebo, and carrier placebo was 12.0 micro m (95% confidence interval [CI], 7.0-17.1 microm), 0.6 micro m (95% CI, -1.0 to 2.2 microm), and 1.3 micro m (95% CI, -0.1 to 2.6 microm), respectively.

CONCLUSION: Application of dorzolamide for 1 day results in a slight but statistically significant thickening of central corneal thickness in patients with cornea guttata.

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Short-term oral pentoxifylline use increases choroidal blood flow in patients with age-related macular degeneration.

Arch. Ophthalmol., 1998; 27-30

OBJECTIVE: To study the ocular hemodynamic effects of a 3-month oral treatment with pentoxifylline in patients with nonexudative age-related macular degeneration.

DESIGN: Double-blind, placebo-controlled, randomized, parallel group study.

SETTING: Outpatient clinic of the Department of Ophthalmology, Vienna University, Vienna, Austria, that specializes in age-related macular degeneration.

METHODS: Forty patients with age-related macular degeneration received pentoxifylline (400 mg 3 times a day orally, n=20) or placebo (n=20) for 3 months. Retinal blood flow was assessed by scanning laser Doppler flowmetry and pulsatile choroidal blood flow was assessed by laser interferometric measurement of fundus pulsation amplitude.

MAIN OUTCOME MEASURES: Changes in retinal blood flow and fundus pulsation amplitude.

RESULTS: Four patients receiving pentoxifylline and 3 patients receiving placebo discontinued medication because of nausea. In the remaining subjects, the use of pentoxifylline increased ocular fundus pulsation amplitude (P<.001 vs placebo and baseline). The maximum increase was 28% after 3 months. In contrast, retinal blood flow was not changed by the use of pentoxifylline.

CONCLUSIONS: A 3-month course of oral pentoxifylline treatment increases choroidal but not retinal blood flow in patients with age-related macular degeneration. These data strongly support the concept that pentoxifylline might be useful in the treatment of age-related macular degeneration. Long-term clinical outcome trials are now warranted to test this hypothesis.

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Statistical problems caused by missing data resulting from neodymium:YAG laser capsulotomies in long-term posterior capsule opacification studies: problem identification and possible solutions.

J Cataract Refract Surg, 2008; 268-73

PURPOSE: To describe a way to eliminate the problem caused by missing data due to neodymium:YAG (Nd:YAG) laser capsulotomies before statistical analysis, which leads to incomplete data in long-term studies of posterior capsule opacification (PCO).

SETTING: Medical University of Vienna, Vienna, Austria.

METHODS: To demonstrate the problem, an existing long-term study comparing PCO development in eyes with round-edged and sharp-edged intraocular lenses (IOLs) was analyzed. In the study, several Nd:YAG capsulotomies led to dropouts in the round-edged IOL group. To solve the resulting missing value problem, the missing values were replaced by estimated PCO values in various scenarios; that is, different assumptions were made of how PCO would have developed without a capsulotomy. Standard statistical analyses that included the estimated PCO values rather than excluding the incomplete cases were then performed.

RESULTS: The analysis of all cases (including the estimated PCO scores) showed a highly significant difference between the round-edged group and the sharp-edged group. Sensitivity analyses confirmed that the difference between the 2 groups remained significant up to highly implausible values chosen for the missing PCO scores, thus proving the correctness of the analysis.

CONCLUSIONS: This study showed it is possible to perform statistical analyses without excluding incomplete cases. This approach is recommended for all studies with Nd:YAG dropouts as it increases the statistical power. Excluding incomplete cases may lead to biased or wrong study conclusions.

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Stereotactic radiotherapy for neovascular age-related macular degeneration: 52-week safety and efficacy results of the INTREPID study.

Ophthalmology, 2013; 1893-900

PURPOSE: To determine the safety and efficacy of low-voltage, external-beam, stereotactic radiotherapy (SRT) for patients with neovascular age-related macular degeneration (nvAMD).

DESIGN: Randomized, double-masked, sham-controlled, multicenter, clinical trial.

PARTICIPANTS: Two hundred thirty patients with onset of nvAMD within 3 years who received 3 or more injections of ranibizumab or bevacizumab within the preceding year and who needed continuing ranibizumab or bevacizumab treatment.

INTERVENTIONS: Participants were randomized 2:1:2:1 to 16 Gy plus pro re nata (PRN) ranibizumab, sham 16 Gy plus PRN ranibizumab, 24 Gy plus PRN ranibizumab, or sham 24 Gy plus PRN ranibizumab, respectively.

MAIN OUTCOME MEASURES: The primary efficacy end point was the mean number of ranibizumab injections at 52 weeks. Secondary end points were change in mean best-corrected visual acuity (VA), loss of fewer than 15 Early Treatment Diabetic Retinopathy Study letters, gain of 0 or more and 15 or more letters, and change in angiographic total lesion size and choroidal neovascularization (CNV) lesion size.

RESULTS: Both the 16-Gy and 24-Gy SRT arms received significantly fewer ranibizumab treatments compared with the sham arms: mean number of treatments, 2.64 (median, 2), 2.43 (median, 2), and 3.74 (median, 3.5), respectively (P = 0.013 and P = 0.004, respectively, vs. sham). Change in mean VA was -0.28, +0.40, and -1.57 letters for the 16-Gy, 24-Gy, and sham arms, respectively. The 16-Gy, 24-Gy, and sham arms lost fewer than 15 letters in 93%, 89%, and 91% of eyes, respectively, with 53%, 57%, and 56% gaining 0 or more letters, respectively, and 4% gaining 15 letters or more in all arms. Mean total angiographic lesion area changed by -1.15 mm(2), +0.49 mm(2), and +0.75 mm(2), respectively; mean CNV lesion area decreased by 0.16 mm(2), 0.18 mm(2), and 0.10 mm(2), respectively. Optical coherence tomography central subfield thickness decreased by 85.90 μm, 70.39 μm, and 33.51 μm, respectively. The number of adverse events (AEs) and number of serious AEs (SAEs) were similar across arms. No AEs were attributed to radiation. No SAEs occurred in the study eye.

CONCLUSIONS: A single dose of SRT significantly reduces ranibizumab retreatment for patients with nvAMD, with a favorable safety profile at 1 year. Whereas chronic nvAMD typically results in loss of VA over time, SRT is associated with relatively well-preserved VA over 1 year.

FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

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Stereotactic radiotherapy for neovascular age-related macular degeneration: year 2 results of the INTREPID study.

Ophthalmology, 2015; 138-45

PURPOSE: To determine the safety and efficacy of low-voltage, external-beam, stereotactic radiotherapy (SRT) for patients with neovascular age-related macular degeneration (AMD).

DESIGN: Randomized, double-masked, sham-controlled, multicenter, clinical trial.

PARTICIPANTS: A total of 230 participants with neovascular AMD who received ≥ 3 ranibizumab or bevacizumab injections within the preceding year and requiring treatment at enrollment.

METHODS: Participants received 16 Gray, 24 Gray, or sham SRT. All arms received pro re nata (PRN) ranibizumab for 12 months, with PRN bevacizumab or ranibizumab thereafter.

MAIN OUTCOME MEASURES: Mean number of PRN injections; best-corrected visual acuity (BCVA); loss of <15 Early Treatment of Diabetic Retinopathy Study letters; change in optical coherence tomography central subfield thickness; and change in angiographic total lesion area and choroidal neovascularization (CNV) area.

RESULTS: At year 2, the 16 and 24 Gray arms received fewer PRN treatments compared with sham (mean 4.5, P = 0.008; mean 5.4, P = 0.09; and mean 6.6, respectively). Change in mean BCVA was -10.0, -7.5, and -6.7 letters for the 16 Gray, 24 Gray, and sham arms, respectively, with 46 (68%), 51 (75%), and 58 participants (79%), respectively, losing <15 letters. Mean central subfield thickness decreased by 67.0 μm, 55.4 μm, and 33.3 μm, respectively. Mean total active lesion area increased by 1.0, 4.2, and 2.7 mm(2), respectively. Mean CNV area decreased by 0.1 mm(2) in all groups. An independent reading center detected microvascular abnormalities in 6 control eyes and 29 SRT eyes, of which 18 were attributed to radiation; however, only 2 of these possibly affected vision. An exploratory subgroup analysis found that lesions with a greatest linear dimension ≤ 4 mm (the size of the treatment zone) and a macular volume greater than the median (7.4 mm(3)) were more responsive to SRT, with 3.9 PRN injections versus 7.1 in comparable sham-treated participants (P = 0.001) and mean BCVA 4.4 letters superior to sham (P = 0.24).

CONCLUSIONS: A single dose of SRT significantly reduces intravitreal injections over 2 years. Radiation can induce microvascular change, but in only 1% of eyes does this possibly affect vision. The best response occurs when AMD lesions fit within the treatment zone and they are actively leaking.

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Stereotactic radiotherapy for wet age-related macular degeneration (INTREPID): influence of baseline characteristics on clinical response.

Retina (Philadelphia, Pa.), 2015; 194-204

PURPOSE: To determine which patients respond best to stereotactic radiotherapy (SRT) for neovascular age-related macular degeneration.

METHODS: Participants (n = 230) receiving intravitreal anti-vascular endothelial growth factor injections for neovascular age-related macular degeneration enrolled in a randomized, double-masked sham-controlled trial comparing 16 Gray, 24 Gray, or Sham SRT. In a post hoc analysis, participants were grouped according to their baseline characteristics, to determine if these influenced SRT efficacy.

RESULTS: At 52 weeks, SRT was most effective for lesions ≤4 mm in greatest linear dimension and with a macular volume greater than the median value of 7.4 mm. For 26% of the participants with both these characteristics, SRT resulted in 55% fewer ranibizumab injections (2.08 vs. 4.60; P = 0.0002), a mean visual acuity change that was 5.33 letters superior to sham (+2.18 vs. -3.15 letters; P = 0.0284), and a 71.1-μm greater reduction in mean central subfield thickness (-122.6 vs. -51.5 μm; P = 0.027). Other features associated with a positive response to SRT included pigment epithelial detachment and the absence of fibrosis.

CONCLUSION: Stereotactic radiotherapy is most effective for neovascular age-related macular degeneration lesions that are actively leaking at the time of treatment, and no larger than the 4-mm treatment zone.

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Stimulus-driven versus pilocarpine-induced biometric changes in pseudophakic eyes.

Ophthalmology, 2005; 453-9

PURPOSE: Most trials that study the lens movement of accommodative intraocular lens (IOLs) use pilocarpine to stimulate ciliary muscle contraction. The aim of this study is to assess in vivo whether a more physiologic, stimulus-driven accommodation is comparable to pilocarpine-induced IOL movement.

DESIGN: Controlled patient- and examiner-masked clinical trial.

PARTICIPANTS: The study population included 38 eyes with accommodative IOL implants (1CU) and a control group of 28 eyes with conventional open-loop IOLs.

METHODS: A high-precision biometry technique, partial coherence interferometry, was used to measure IOL position. Anterior chamber depth was measured during physiologic (near point) and pharmacological (pilocarpine 2%) stimulation. In a subgroup of 14 1CU eyes, IOL position was determined repeatedly within 90 minutes after pilocarpine administration. A different subgroup was investigated as to the effect of cyclopentolate on IOL position. Best-corrected distance visual acuity (VA), best-corrected near VA, and distance-corrected near VA (DCNVA) were assessed using logarithm of the minimum angle of resolution charts.

MAIN OUTCOME MEASURES: Anterior chamber depth change under pilocarpine and near-point-driven accommodation.

RESULTS: Near-point accommodation did not induce movement of either the accommodating 1CU or the control IOLs. Pilocarpine induced a 201+/-0.137-mm anterior movement of the 1CU IOL (P<0.001), compared with no movement within the control IOL groups (P>0.05). There was no significant (P>0.05) difference in DCNVA between the accommodative and open-loop IOLs. No correlation between near point- or pilocarpine-stimulated IOL movement and DCNVA was found. Concerning the time course of movement after pilocarpine administration, most of the 1CU IOLs showed some movement 30 minutes after application. Cyclopentolate-induced ciliary muscle relaxation caused a posterior IOL movement, as compared with the relaxed state, when focusing on a distant target.

CONCLUSION: Pilocarpine-induced ciliary muscle contraction seems to overestimate IOL movement relative to a monocular near-driven stimulus. Therefore, concerning IOL movement, pilocarpine may act as a superstimulus and may not adequately simulate daily life performance of accommodative IOLs. However, it may be helpful to evaluate the maximum potential of an accommodating IOL.

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A study comparing ocular pressure pulse and ocular fundus pulse in dependence of axial eye length and ocular volume.

Acta Ophthalmol, 2010; 766-72

PURPOSE: There is a long-standing discussion about whether myopia is associated with decreased choroidal blood flow, as suggested by pneumotonometric measurements of pulsatile ocular blood flow (POBF). However, it has been noted previously that calculations of POBF depend on intraocular volume.

METHODS: In the present study we investigated this volume dependence through the comparison of ocular pressure pulse and ocular fundus pulse. Fifty-one healthy participants with different refractive errors participated in the study. Pulse amplitude (PA) and POBF were measured using pneumotonometry. Fundus pulsation amplitude (FPA) was measured with laser interferometry. Axial eye length (AEL) was measured with partial coherence interferometry. A mathematical model was used to calculate choroidal volume changes based on FPA. The ocular pressure pulse was converted into pulse volume (PV) according to the standard procedure used for pneumotonometry.

RESULTS: PA and POBF were found to decrease with increasing axial length (r = -0.55, p < 0.001 and r = -0.57, p < 0.001, respectively). A similar relationship existed for PV (r = -0.57, p < 0.001) and FPA (r = -0.46, p = 0.001). In addition, there was a significant association between PV and choroidal volume change during the cardiac cycle (r = 0.61, p < 0.001).

CONCLUSION: The present study confirms experimentally that PA, FPA and POBF are dependent on ocular volume and indicates that the pulsatile component of ocular blood flow is not reduced in myopic patients. Accordingly, the relationship between AEL and POBF described previously appears to be a consequence of different ocular volumes. Our findings have important implications for studies using PA or POBF.

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Submicrometer precision biometry of the anterior segment of the human eye.

Invest. Ophthalmol. Vis. Sci., 1997; 1304-13

PURPOSE: To demonstrate the feasibility of measuring the anterior structures of the human eye by partial coherence interferometry and to determine its precision for eyes under normal and cycloplegic conditions.

METHODS: The dual-beam version of partial coherence interferometry, a recently developed noninvasive optical ranging technique, enables high resolution measurements of several intraocular distances with unprecedented precision. A modified, more sensitive scanning version of this technique was used to assess the central and peripheral corneal thickness, the anterior chamber depth, and the lens thickness of 20 healthy, emmetropic to moderately myopic eyes. Furthermore the anterior structures of three eyes were measured under cycloplegia (1% cyclopentolate) to investigate the influence on the precision of this technique after suppression of residual accommodations.

RESULTS: The mean geometric precision (standard deviation) of the measurement of the central corneal thickness was 0.29 micron (range, 0.22 micron to 0.38 micron) and 0.43 micron (range, 0.27 micron to 0.56 micron) for the peripheral corneal thickness at a distance 2 mm from its apex. The precision for measuring the anterior chamber depth and the lens thickness for fixation at infinity was 8.7 microns (range, 3.9 microns to 16.8 microns) and 8.9 microns (rang, 2.9 microns to 14.4 microns) for noncycloplegic eyes and 1.9 microns (range, 1.7 microns to 2 microns) and 1.4 microns (range, 0.7 micron to 1.8 microns) for cycloplegic eyes, respectively.

CONCLUSIONS: The dual-beam partial coherence interferometry enables fast, noninvasive, submicrometer precision biometry of the anterior segment of the eye. The precision of determining the anterior chamber depth and the lens thickness is more than one order of magnitude better than that of the currently used ultrasound and optical techniques, and it can be improved by a factor of 5 by using cycloplegia.

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Ten years of intraoperative floppy iris syndrome in the era of α-blockers.

Cent European J Urol, 2018; 98-104

Introduction: The use of alpha-1 receptor antagonists in the treatment of benign prostatic hyperplasia (BPH) has created a problem in ophthalmic surgery, the so-called intraoperative floppy iris syndrome (IFIS). This consists of a billowing iris, insufficient pupillary dilation with progressive intraoperative miosis, and protrusion of iris tissue through the tunnel and side port incision that are made for access to the anterior chamber during surgery. IFIS presents particular difficulties in cataract surgery which is carried out through the pupil with manipulations in the immediate vicinity of the iris. The complications range from poor visibility of the operative field to iris damage with the surgical instruments and to rupture of the posterior capsule, with loss of lens material into the vitreous body.

Material and methods: A comprehensive literature review was performed using MEDLINE with MeSH terms and keywords 'benign prostatic hyperplasia', 'intraoperative floppy iris syndrome', 'adrenergic alpha-antagonist' and 'cataract surgery'. In addition, reference lists from identified publications were reviewed to identify reports and studies of interest from 2001 to 2017.

Results: The A total of 95% of experienced ophthalmologic surgeons reported that systematic treatment with tamsulosin represents a challenging surgical condition increasing the risk of complications. Alpha-blockers are commonly prescribed, with 1,079,505 packages of tamsulosin prescribed each month in 2014 in Austria. Dose modification may be one way to reduce the risk of IFIS. A lower incidence of IFIS was reported in patients on tamsulosin in Japan, but the recommended dosage was lower than that used in Europe and the US (0.2 mg vs. 0.4 mg).

Conclusions: We showed that not all patients taking tamsulosin experience IFIS. Moreover, larger investigations with a prospective design are needed, including studies to monitor the pre- and post-therapeutic ophthalmologic changes under tamsulosin, as well as urodynamic improvements resulting from this therapy.

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Test-Retest Reproducibility of the Microperimeter MP3 With Fundus Image Tracking in Healthy Subjects and Patients With Macular Disease.

Transl Vis Sci Technol, 2018; 17

Purpose: To evaluate the test-retest reproducibility of a novel microperimeter with fundus image tracking (MP3, Nidek Co, Japan) in healthy subjects and patients with macular disease.

Methods: Ten healthy subjects and 20 patients suffering from range of macular diseases were included. After training measurements, two additional microperimetry measurements were scheduled. Test-retest reproducibility was assessed for mean retinal sensitivity, pointwise sensitivity, and deep scotoma size using the coefficient of repeatability and Bland-Altman diagrams. In addition, in a subgroup of patients microperimetry was compared with conventional perimetry.

Results: Average differences in mean retinal sensitivity between the two study measurements were 0.26 ± 1.7 dB (median 0 dB; interquartile range [IQR] -1 to 1) for the healthy and 0.36 ± 2.5 dB (median 0 dB; IQR -1 to 2) for the macular patient group. Coefficients of repeatability for mean retinal sensitivity and pointwise retinal sensitivity were 1.2 and 3.3 dB for the healthy subjects and 1.6 and 5.0 dB for the macular disease patients, respectively. Absolute agreement in deep scotoma size between both study days was found in 79.9% of the test loci.

Conclusion: The microperimeter MP3 shows an adequate test-retest reproducibility for mean retinal sensitivity, pointwise retinal sensitivity, and deep scotoma size in healthy subjects and patients suffering from macular disease. Furthermore, reproducibility of microperimetry is higher than conventional perimetry.

Translational Relevance: Reproducibility is an important measure for each diagnostic device. Especially in a clinical setting high reproducibility set the basis to achieve reliable results using the specific device. Therefore, assessment of the reproducibility is of eminent importance to interpret the findings of future studies.

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Topical fundus pulsation measurements in age-related macular degeneration.

Graefes Arch. Clin. Exp. Ophthalmol., 1998; 160-3

BACKGROUND: The purpose of the present study was to investigate regional fundus pulsations in age-related macular degeneration (AMD) patients with subretinal neovascular membranes.

METHODS: Local fundus pulsation amplitudes (FPAs) were measured in 12 patients with AMD with classic neovascular membranes. Measurements were performed directly on the membrane and adjacent to the membrane. FPAs were assessed with a recently developed laser interferometric method. FPA measurements were performed in 12 healthy subjects at similar posterior pole locations.

RESULTS: In AMD patients FPAs were consistently lower when measured directly on the neovascular membrane ("inside") than at measurement sites around the membrane ("outside"). The difference in FPA was 26 +/- 3% (mean +/- SEM, range 13-40%, P < 0.0001). In healthy subjects, however, FPAs were significantly higher at the measurement points corresponding to "inside" points (15 +/- 4%, P < 0.0006).

CONCLUSIONS: We have shown that FPAs are reduced at classic neovascular membranes in patients with AMD. The mechanism behind this finding remains unclear. Hence, future studies have to ascertain whether this observation is associated with changes in fundus layers or with local choroidal perfusion abnormalities.

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Track W. Personalized Health.

Biomed Tech (Berl), 2016; 245-246

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Twelve hour reproducibility of choroidal blood flow parameters in healthy subjects.

Br J Ophthalmol, 2004; 533-7

AIMS/BACKGROUND: To investigate the reproducibility and potential diurnal variation of choroidal blood flow parameters in healthy subjects over a period of 12 hours.

METHODS: The choroidal blood flow parameters of 16 healthy non-smoking subjects were measured at five time points during the day (8:00, 11:00, 14:00, 17:00, and 20:00). Outcome parameters were pulsatile ocular blood flow as assessed by pneumotonometry, fundus pulsation amplitude as assessed by laser interferometry, blood velocities in the opthalmic and posterior ciliary arteries as assessed by colour Doppler imaging, and choroidal blood flow, volume, and velocity as assessed by fundus camera based laser Doppler flowmetry. The coefficient of variation and the maximum change from baseline in an individual were calculated for each outcome parameter.

RESULTS: None of the techniques used found a diurnal variation in choroidal blood flow. Coefficients of variation were within 2.9% and 13.6% for all outcome parameters. The maximum change from baseline in an individual was much higher, ranging from 11.2% to 58.8%.

CONCLUSIONS: These data indicate that in healthy subjects the selected techniques provide adequate reproducibility to be used in clinical studies. Variability may, however, be considerably higher in older subjects or subjects with ocular disease. The higher individual differences in flow parameter readings limit the use of the techniques in clinical practice. To overcome problems with measurement validity, a clinical trial should include as many choroidal blood flow outcome parameters as possible to check for consistency.

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Using continuous intraoperative optical coherence tomography measurements of the aphakic eye for intraocular lens power calculation.

Br J Ophthalmol, 2015; 7-10

BACKGROUND/AIMS: To include intraoperative measurements of the anterior lens capsule of the aphakic eye into the intraocular lens power calculation (IPC) process and to compare the refractive outcome with conventional IPC formulae.

METHODS: In this prospective study, a prototype operating microscope with an integrated continuous optical coherence tomography (OCT) device (Visante attached to OPMI VISU 200, Carl Zeiss Meditec AG, Germany) was used to measure the anterior lens capsule position after implanting a capsular tension ring (CTR). Optical biometry (intraocular lens (IOL) Master 500) and ACMaster measurements (Carl Zeiss Meditec AG, Germany) were performed before surgery. Autorefraction and subjective refraction were performed 3 months after surgery. Conventional IPC formulae were compared with a new intraoperatively measured anterior chamber depth (ACD) (ACDIntraOP) partial least squares regression (PLSR) model for prediction of the postoperative refractive outcome.

RESULTS: In total, 70 eyes of 70 patients were included. Mean axial eye length (AL) was 23.3 mm (range: 20.6-29.5 mm). Predictive power of the intraoperative measurements was found to be slightly better compared to conventional IOL power calculations. Refractive error dependency on AL for Holladay I, HofferQ, SRK/T, Haigis and ACDintraOP PLSR was r(2)=-0.42 (p<0.0001), r(2)=-0.5 (p<0.0001), r(2)=-0.34 (p=0.010), r(2)=-0.28 (p=0.049) and r(2)<0.001 (p=0.866), respectively,

CONCLUSIONS: ACDIntraOP measurements help to better predict the refractive outcome and could be useful, if implemented in fourth-generation IPC formulae.

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Using continuous intraoperative optical coherence tomography to classify swirling lens fragments during cataract surgery and to predict their impact on corneal endothelial cell damage.

J Cataract Refract Surg, 2016; 1029-36

PURPOSE: To quantify and classify swirling lens fragments during cataract surgery and record their impact on the corneal endothelium using continuous intraoperative optical coherence tomography (OCT).

SETTING: Vienna Institute for Ocular Surgery, Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective case series.

METHODS: Patients scheduled for cataract surgery without other ophthalmologic comorbidities were included. During surgery, continuous OCT recordings were performed to measure and score swirling lens fragments that came into contact with the corneal endothelium. Endothelial cell density (ECD) was measured preoperatively and 1 month postoperatively. In addition, the central corneal thickness and aqueous flare were measured preoperatively and 1 hour, 1 day, and 1 month postoperatively.

RESULTS: Continuous intraoperative OCT video recordings showed 104 swirling lens fragments in 40 eyes that came into contact with the corneal endothelium. A mean of 2.6 lens fragments (range 0 to 6) that came into contact were observed per eye. Small fragments and fragments touching the center of the endothelium had a significantly greater effect on postoperative ECD than other fragment parameters. The predictive power of the fragment score on ECD was found to be moderate (r(2) = 0.6).

CONCLUSIONS: Small swirling lens fragments touching the center of the corneal endothelium had a significant influence on ECD. With the newly developed fragment score, it was possible to predict the operative endothelial cell loss.

FINANCIAL DISCLOSURE: None of the authors has a financial or proprietary interest in any material or method mentioned.

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Value of polarisation-sensitive optical coherence tomography in diseases affecting the retinal pigment epithelium.

Br J Ophthalmol, 2008; 204-9

OBJECTIVES: To evaluate pathological changes of retinal pigment epithelium (RPE) by polarisation-sensitive optical coherence tomography (PS-OCT).

METHODS: Forty-four eyes (22 patients) with significant pathologies of the RPE were evaluated using PS-OCT. A transversal scanning time domain OCT system was used for two-dimensional cross-sectional imaging of retinal polarisation properties.

RESULTS: The RPE scrambles the polarisation state of backscattered light (ie, acts as a depolarising layer), while the polarisation state of transmitted light is maintained. In patients with RPE pathologies irregularity, elevation, thickening or absence of the RPE is readily visualised by exploiting the depolarisation information. Polarisation scrambling in the sensory retina can be found in cases with advanced dry age-related macular degeneration. Sclera and fibrosis show characteristic birefringence in PS-OCT.

CONCLUSION: PS-OCT allows tissue identification based on polarisation scrambling and birefringence, providing additional information on RPE pathologies. It is a promising new tool for diagnosis, disease follow-up and evaluation of new treatment strategies.

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Variability in angle κ and its influence on higher-order aberrations in pseudophakic eyes.

J Cataract Refract Surg, 2017; 1015-1019

PURPOSE: To observe the variability in angle κ in pseudophakic patients and assess its correlation with optical biometry measurements and higher-order aberrations (HOAs).

SETTING: Hanusch Hospital, Vienna, Austria.

DESIGN: Prospective case series.

METHODS: This study included patients who had cataract surgery 3 months to 1 year before study recruitment. In all cases, Purkinje meter images were taken. In addition, partial coherence interferometry measurement (IOLMaster) of the axial intraocular lens (IOL) position was performed. In a subgroup of patients, an additional Hartmann-Shack sensor measurement was taken to assess HOAs (WASCA).

RESULTS: This study comprised 395 eyes of 349 patients. The mean age of the 210 women and 139 men was 74.1 years ± 8.6 (SD) (range 44 to 91 years). The mean tilt (pupillary axis) and decentration were 3.9 ± 2.3 degrees (range 0.2 to 16.2 degrees) and 0.4 ± 0.2 mm (range 0.0 to 1.7 mm), respectively. The mean angle κ was 5.2 ± 2.6 degrees (range 0.3 to 13.9 degrees), and the mean orientation of this modulus was 189.5 ± 53.2 degrees (range 25.3 to 339.7 degrees).

CONCLUSION: The variability in the angle κ was high.

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Visualizing Macular Structures During Membrane Peeling Surgery With an Intraoperative Spectral-Domain Optical Coherence Tomography Device.

Ophthalmic Surg Lasers Imaging Retina, 2016; 328-32

BACKGROUND AND OBJECTIVE: The aim of this study was to examine the quality of intraoperative visualization of the posterior hyaloid, epiretinal membrane (ERM), inner limiting membrane (ILM), and hyporeflective subfoveal zone with a commercially available, microscope-integrated spectral-domain OCT setup (mi-SD-OCT) (Rescan 700; Carl Zeiss Meditec AG, Germany).

PATIENTS AND METHODS: Twenty patients prospectively scheduled for pars plana vitrectomy with membrane peeling due to an idiopathic ERM were included. Standard 23-gauge, three-port pars plana vitrectomy with membrane peeling and staining of the ERM with a trypan blue-based chromovitrectomy dye was performed in all cases. Intraoperative SD-OCT was performed before and after peeling and visualization of the posterior hyaloid, ERM, ILM, and presence of subfoveal hyporeflective zones were examined. OCT follow-ups were performed 2 days and 3 months after surgery. The study was approved by the local ethics committee of the city of Vienna.

RESULTS: Successful intraoperative visualization of ERM by mi-SD-OCT was possible in all cases. The posterior hyaloid and ILM could not be seen in the mi-SD-OCT scans, whereas an intraoperative subfoveal hyporeflective zone presented in 35% of cases. In 12.5% an independent subfoveal hyporeflective zone presented postoperatively. Visual acuity improved in 93.8% of patients after surgery.

CONCLUSION: mi-SD-OCT appears to be a valuable tool for intraoperative visualization of the ERM and offers immediate visualization of retinal anatomy during peeling. Therefore, it adds to the understanding of intraoperative traumatic changes due to the peeling procedure.

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WITHDRAWN: Interventions for normal tension glaucoma.

Cochrane Database Syst Rev, 2010; CD002222

BACKGROUND: Normal tension glaucoma is a clinical condition in which the optic nerve is pathologically excavated and the visual field is disturbed. Nevertheless it has been assumed that intraocular pressure plays a role in the progression of visual field defects in this disease, but other, mainly vascular factors, have been discussed as well.

OBJECTIVES: The objective of this review is to assess the effects of medical and surgical treatments for normal tension glaucoma.

SEARCH STRATEGY: Trials were identified from the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Group trials register), MEDLINE, EMBASE and BIOSIS Previews. Bibliographies of identified trials were searched to find additional trials. In addition, investigators and pharmaceutical companies were contacted. Date of last search: January 2001.

SELECTION CRITERIA: This review includes randomised controlled trials in which medical or surgical interventions were compared to no treatment, placebo or other treatment in people with normal tension glaucoma.

DATA COLLECTION AND ANALYSIS: Data were extracted by two reviewers and results were compared for differences. Discrepancies were resolved by discussion. The heterogeneity of interventions, follow-up periods and outcomes did not allow for statistical combinations of the study results.

MAIN RESULTS: According to the selection criteria on visual field loss, eight studies were included in this review. Only three studies focussed on patient relevant outcomes. In one trial a beneficial effect of lowering intraocular pressure was found, but only if data were corrected for cataract development. In two small studies a beneficial effect on visual field loss of brovincamine, a calcium antagonist was reported.

AUTHORS' CONCLUSIONS: In one study the effect of intraocular pressure lowering on visual field outcome was only significant when data were corrected for cataract development. The results for calcium antagonists are promising, but larger trials have to be performed. Studies that focussed on reduction of intraocular pressure or haemodynamic variables are not necessarily relevant for the outcome in people with normal tension glaucoma.

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