Wolf Buehl

Comparison of 4 methods for quantifying posterior capsule opacification.

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.

Long-term effect of optic edge design in an acrylic intraocular lens on posterior capsule opacification

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.

Pilocarpine-induced shift of an accommodating intraocular lens: AT-45 Crystalens

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 μm in the nonpolished group (P<.001) and 122 μm 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.

Effect of dorzolamide and timolol on ocular blood flow in patients with primary open angle glaucoma and ocular hypertension

Background: There is evidence that perfusion abnormalities of the optic nerve head are involved in the pathogenesis of glaucoma. There is therefore considerable interest in the effects of topical antiglaucoma drugs on ocular blood flow. A study was undertaken to compare the ocular haemodynamic effects of dorzolamide and timolol in patients with primary open angle glaucoma (POAG) or ocular hypertension (OHT). Methods: One hundred and forty patients with POAG or OHT were included in a controlled, randomised, double blind study in two parallel groups; 70 were randomised to receive timolol and 70 to receive dorzolamide for a period of 6 months. Subjects whose intraocular pressure (IOP) did not respond to either of the two drugs were switched to the alternative treatment after 2 weeks. Scanning laser Doppler flowmetry was used to measure blood flow in the temporal neuroretinal rim and the cup of the optic nerve head. Pulsatile choroidal blood flow was assessed using laser interferometric measurement of fundus pulsation amplitude. Results: Five patients did not respond to timolol and were changed to the dorzolamide group, and 18 patients changed from dorzolamide treatment to timolol. The effects of both drugs on IOP and ocular perfusion pressure were comparable. Dorzolamide, but not timolol, increased blood flow in the temporal neuroretinal rim (8.5 (1.6)%, p<0.001 versus timolol) and the cup of the optic nerve head (13.5 (2.5)%, p<0.001 versus timolol), and fundus pulsation amplitude (8.9 (1.3)%, p<0.001 versus timolol). Conclusions: This study indicates augmented blood flow in the optic nerve head and choroid after 6 months of treatment with dorzolamide, but not with timolol. It remains to be established whether this effect can help to reduce visual field loss in patients with glaucoma.

Effect of intraocular lens design on posterior capsule opacification

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.

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

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 (mm2) 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.

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

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.

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

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.

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

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 (mm2). 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.

Rotational stability and posterior capsule opacification of a plate-haptic and an open-loop-haptic intraocular lens

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. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.