Effect of intraocular lens edge profile on posterior capsule opacification after extracapsular cataract surgery in a developing country

PURPOSE: To determine whether square-edged polymethyl methacrylate (PMMA) intraocular lenses (IOLs) reduce posterior capsule opacification (PCO) in the context of extracapsular cataract surgery in a developing country. SETTING: A rural hospital in India. METHODS: This was a prospective randomized double-masked fellow-eye controlled study. Over a 4-month period, 118 patients with normal eyes apart from age-related cataract were randomized to receive a square-edged or round-edged PMMA IOL in the first eye. The IOLs were identical apart from the edge profile. The fellow-eye had implantation of the alternative IOL within 1 month. Retroillumination images of the posterior capsule were taken using a dedicated camera system and analyzed to quantify the PCO area using POCO software 1 and 2 years postoperatively and the PCO area and severity using POCOman semiqualitative software at 2 years. Visual acuity was measured using a Gujarati logMAR chart. RESULTS: One hundred fifteen patients were available for examination at 1 year and 107 at 2 years. With POCO software, the PCO area was reduced in the square-edged IOL group at 1 year (median 30% versus 20%, P=.001) and at 2 years (median 45% versus 35%, P=.006). With POCOman, the PCO area and severity were reduced in the square-edged group at 2 years (median 41.5% versus 33.2%, P=.019 and 0.59 versus 0.46, P=.037, respectively). There was no significant difference in visual acuity between the 2 groups at 1 or 2 years. CONCLUSIONS: Sophisticated image analysis techniques can be used in developing countries to quantify PCO. Using extracapsular surgery, square-edged PMMA IOLs reduced the PCO area and severity compared with an identical round-edged IOL; however, the differences were not as marked as those reported with phacoemulsification. This may be due to the difficulty of performing a capsulorhexis that lies on the IOL surface in this situation. Nevertheless, square-edged IOLs offer a potential benefit for extracapsular surgery in the developing world.     

Posterior capsule opacification after extra capsular cataract extraction in Indian rural population: foldable acrylic vs poly (methyl-methacrylate) intraocular lenses a randomized clinical trial

PURPOSE: To compare the performance of single-piece acrylic vspoly (methylmethacrylate) intraocular lenses (IOL) on the development of posterior capsule opacification (PCO) after conventional extra capsular cataract extraction (ECCE). MATERIALS AND METHODS: One hundred and eighty-two eyes of 91 patients with bilateral senile cataract undergoing ECCE were prospectively randomized to receive a single-piece Alcon AcrySof SA60AT IOL or a single-piece EPOCH polymethylmethacrylate IOL in the first eye to have surgery. At 1, 6 and 12 months post-operative follow-up, digital retro illumination images of the posterior capsule were taken for PCO assessment semi-objectively using PCO (POCO automated analysis software) system. Relationship of anterior capsule contact (total off and partial cover) on optic for PCO was analyzed. RESULTS: The AcrySof IOL was associated with less PCO than EPOCH lens at 6 months (10.01+/-8.75% vs 32.26+/-27.44%; P<0.001) and 1-year (11.65+/-10.55% vs 38.38+/-29.62%; P<0.001) follow-up. The EPOCH IOL showed a remarkably significant difference on development of PCO with anterior capsule overlap on IOL optic (total off and part on) 1 year (P<0.039), whereas no such difference was observed with the AcrySof IOL (P=0.197). CONCLUSION: The AcrySof IOL led to significantly less PCO than the EPOCH IOL post-operatively after extracapsular cataract extraction.     

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.     

白内障术后后囊膜混浊的量化分析(英文)

目的:评估白内障术后疏水性丙烯酸人工晶状体Sensar AR40e和硅胶人工晶状体的后囊膜混浊(PCO),并用能客观评估PCO的软件量化分析。方法:共选择98眼行标准的超声乳化白内障吸除术,人工晶状体囊袋内固定。所有眼随机植入Sensar AR40e或硅胶人工晶状体,但同一患者植入的人工晶状体必须不同。在第1～2a时后照法拍摄后囊膜图像,通过去除浦肯野反光、增强对比度、过滤后增强低密度的PCO等方法处理后用POCO软件分析对比。结果:术后1a疏水性丙烯酸人工晶状体PCO百分比为0.32±0.13,硅胶人工晶状体为0.39±0.17(P=0.37)。2a时疏水性丙烯酸人工晶状体PCO百分比为0.42±0.20,硅胶晶状体为0.34±0.18(P=0.50)。患者术后1,2a时疏水性丙烯酸人工晶状体PCO的严重级别分别是0.50±0.30和0.82±0.58,与硅胶人工晶状体的0.63±0.35和0.55±0.35相比,无统计学意义(P=0.52,P=0.69)。结论:POCO后囊膜混浊量化分析系统提供了客观而且可重复性强的量化PCO的方法,也是研究预防PCO技术的有力工具。     

Fellow-eye comparison of posterior capsule opacification rates after implantation of 1CU accommodating and AcrySof MA30 monofocal intraocular lenses

PURPOSE: To measure posterior capsule opacification (PCO) and neodymium:YAG (Nd:YAG) capsulotomy rates between the AcrySof MA30 intraocular lens (IOL) (Alcon) and the 1CU IOL (HumanOptics) in a fellow-eye comparison. SETTING: Ophthalmology Department, St. Thomas' Hospital, London, United Kingdom. METHODS: Thirty patients who had bilateral cataract surgery with a 1CU IOL prospectively randomly allocated to 1 eye and an AcrySof MA30 monofocal IOL to the other eye were examined. Best corrected distance visual acuity was recorded using the Early Treatment Diabetic Retinopathy Study logMAR chart. Digital retroillumination images of the posterior capsule were taken with the pupil dilated and analyzed with POCO software. RESULTS: Eyes with the 1CU IOL had significantly higher PCO rates than eyes with the MA30 IOL at all time points. By 2 years after surgery, 50% of eyes with a 1CU IOL had required Nd:YAG capsulotomy compared with no eyes with an MA30 IOL. There was no significant difference in visual acuity at any time point when post Nd:YAG capsulotomy was taken in to account. CONCLUSIONS: The 1CU IOL has 4 broad optic-haptic junctions where the square-edged barrier is breached; this appeared to allow passage of lens epithelial cells, leading to an increase in PCO. However, the increased PCO cannot be attributed to this alone as the 1CU is hydrophilic, a factor known to be associated with higher PCO rates.     

白内障手术后后囊膜混浊的量化比较

目的 评估白内障术后疏水件丙烯酸人工晶状体SensarAR40e和硅胶人工晶状体的后囊膜混浊(PCO),并用能客观评估PCO的软件量化分析.方法 共选择98只眼行标准的超声乳化白内障吸除术,人工晶状体囊袋内固定.所有眼随机植入Sensar AR40e或硅胶人工晶状体,但同一患者植入的人工晶状体必须不同.在第1年和第2年时后照法拍摄后囊膜图像,通过去除浦肯野反光、增强对比度、过滤后增强低密度的PCO等方法处理后用POCO软件分析对比.结果 术后1年疏水性丙烯酸人工晶状体PCO为(0.32±0.13)%硅胶人工晶状体为(0.39±0.17)%(P=0.37).2年时疏水性丙烯酸人工晶状体PCO为(0.42±0.20)%,硅胶品状体为(0.34±0.18)%(P=0.50).患者术后1年,2年时疏水性丙烯酸人工品状体PCO的严重级别分别是(0.50±0.30)和(0.82±0.58),‘亏硅胶人工晶状体的(0.63±0.35)和(0.55±0.35)相比,无统计学意义(P＜0.05).结论 PCO后囊膜混浊量化分析系统提供了客观而且可重复性强的量化PCO的方法,也是研究预防PCO技术的有力工具.     

Correlation between the measurement of posterior capsule opacification severity and visual function testing

PURPOSE: To develop software to measure the severity of posterior capsule opacification (PCO) using analysis of retroillumination images and to correlate the results with clinical evaluation of PCO severity and visual function. SETTING: Department of Physics, King's College, and Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom. METHODS: A technique for calculating PCO severity was developed based on calculating the variance of intensity by transforming retroillumination images to a similar mean intensity. The computer-derived severity was compared to grading of clinical severity by 3 independent observers using a library of 100 retroillumination images ranging from clear posterior capsules to very severe PCO. The computer results were also compared with the following other current methods of measuring PCO: Evaluation of Posterior Capsule Opacification (EPCO), POCOman, and Automated Quantification of After-Cataract. A further 35 images were used to compare the results of computer-derived severity with the results of visual function analysis (high-contrast acuity, 100%; low-contrast acuity, 9%) using the Early Treatment Diabetic Retinopathy Study chart, contrast sensitivity testing using the Pelli-Robson chart, and glare assessment using the van den Berg straylight meter. RESULTS: The severity scores showed a good correlation with clinical severity scores for the library of images (r=0.86) and with severity scores using POCOman and EPCO (r=0.85 and r=0.81, respectively). The correlations with visual function tests were also good, with low-contrast visual acuity (9%) showing the best correlation (r=0.87). CONCLUSION: Variance in intensity of PCO was successfully used to calculate the severity of PCO.     

Factors that influence the development of posterior capsule opacification with a polyacrylic intraocular lens

PURPOSE: To identify factors that contribute to posterior capsule opacification (PCO) after implantation of a 5.5 mm polyacrylic (IOL). DESIGN: A retrospective analysis of a cohort of sequential images taken from the PCO database at St. Thomas' Hospital, London, to include all patients with an AcrySof MA30 lens and a 1-year retroillumination image. METHODS: Records of age, gender, axial length, and PCO measurements using the POCO software system were available. Images were divided into those with greater or less than 10% PCO. The degree of rhexis-IOL contact was recorded in clock hours. RESULTS: Images of 60 eyes were analyzed. Twenty-one eyes had more than 10% PCO. No correlation was found between PCO and age, gender, or axial length. Forty-eight eyes (80%) had some loss of rhexis-IOL contact. These eyes had increased PCO (P < .001) compared with eyes with complete IOL-rhexis contact. More PCO developed when the rhexis was partly on and partly off the IOL. CONCLUSIONS: PCO is reduced when the rhexis is in complete contact with the anterior IOL surface. The failure to achieve this accounts for the majority of increased PCO seen in patients implanted with this IOL model. PCO formation is related to surgical technique as well as IOL design, and comparisons cannot be made between IOLs without taking this into consideration. These results support the trend to the use of larger optic IOLs to prevent PCO and also support the "capsule compression" theory of PCO prevention.     

Influences of optic edge design on posterior capsule opacification and anterior capsule contraction

PURPOSE: To investigate the influence of optic edge design on posterior capsule opacification (PCO) and anterior capsule contraction (ACC). METHODS: A total of 43 eyes of 43 patients scheduled to undergo cataract surgery were included in this study. Patients received either a Sensor AR40 intraocular lens (IOL) or a Sensor AR40e IOL. The area of the anterior capsule opening (ACO) was determined by diaphanoscopy using the anterior eye segment analysis system EAS-1000 at 1 day, 1 week and 1, 3, 6 and 12 months postoperatively. Posterior capsule opacification was evaluated objectively in two ways, using either the EAS-1000 or POCOman. RESULTS: There was no significant difference between the two groups in either ACO area or percentage reduction of ACO area at any time-point after surgery. The difference in the degree of PCO 1 year after surgery was not significant when measured by either the EAS-1000 or POCOman. CONCLUSIONS: A sharp IOL edge is required to prevent PCO. Sharp-edged IOLs do not appear to be a risk factor for ACC.     

Effect of an acrylic intraocular lens with a sharp posterior optic edge 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) (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.     

Effect of surface coating an acrylic intraocular lens with poly(2-methacryloyloxyethyl phosphorylcholine) polymer on lens epithelial cell line behavior

PURPOSE: To evaluate the effect of surface coating of an acrylic intraocular lens (IOL) with poly(2-methacryloyloxyethyl phosphorylcholine) (MPC) on the behavior of the lens epithelial cell (LEC) line, alpha-TN4. SETTING: Department of Ophthalmology, Nihon University School of Medicine, Tokyo, Japan. METHODS: A hydrophobic soft acrylic IOL (AF-1, Hoya) was coated with MPC polymer. A noncoated IOL served as control. An IOL from each group was placed on the membrane of collagen I or IV of the cell culture dish. The alpha-TN4 cells were seeded in the insert. Cell behaviors (ie, cell proliferation and spreading) on IOLs and membranes were observed. Cell migration beneath the IOL optic portion was assayed using a computer software program (POCOman system) for posterior capsule opacification (PCO). Type I or IV collagen is the major matrix component of PCO or native lens capsule. RESULTS: Cell proliferation was more marked on the noncoated IOL than on the coated IOL. Type IV collagen accelerated proliferation more than type I collagen. Cell migration to the area beneath the IOL optic was more prominent in the group with the type I collagen membrane and noncoated IOL than in other groups. CONCLUSION: Coating an acrylic IOL surface with MPC polymer suppressed adhesion and proliferation of LECs, suggesting it improves IOL biocompatibility.     

Predicting posterior capsule opacification: value of early retroillumination imaging

PURPOSE: To investigate the value of early retroillumination imaging of the posterior capsule in predicting the eventual development of posterior capsule opacification (PCO). SETTING: Ophthalmology Department, St. Thomas' Hospital, and Department of Physics, King's College, London, United Kingdom. METHODS: All patients with retroillumination images of the posterior capsule taken 6 months and 2 years after uneventful phacoemulsification with in-the-bag intraocular lens (IOL) implantation were selected. The images were taken using the same hardware and analyzed with the same software to calculate the percentage area of the posterior capsule covered by lens epithelial cells. The percentage area of PCO with all IOL types 6 months postoperatively was correlated with that at 2 years. RESULTS: One hundred forty patients had analyzable images at 6 months and 2 years. Of these, 63 had a poly(methyl methacrylate) (PMMA) IOL (Pharmacia 812A or Storz P497UV), 33 an acrylic (Alcon AcrySof MA30 or SA30), 22 a silicone (Allergan SI-30), and 22 a hydrophilic acrylic (Bausch & Lomb Hydroview H60). The correlation of the percentage area of PCO at 6 months with that at 2 years resulted in an r value of 0.71 (P <.0001) in the entire group. The r value was 0.48 in the PMMA group and 0.86 in the foldable IOL group (P <.0001) (r value: AcrySof, 0.66; silicone, 0.82; Hydroview, 0.75). CONCLUSIONS: Retroillumination imaging of the posterior capsule 6 months after cataract surgery predicted the PCO outcome at 2 years in eyes with foldable IOLs.     

后发性白内障形态及对视功能影响临床分析

目的 通过对后发性白内障(Posterior Capsule Opacification,PCO)的形态学及其对视功能影响的客观综合评价,为临床激光后囊切开术提供指导意义.方法 选择61例(67只眼)后发性白内障拟行Nd:YAG 激光后囊切开术的患者,充分散大瞳孔(直径>6.00mm),先采用裂隙灯加前置镜行主观评价,再行裂隙灯眼底后部反光裂隙照相,所得数码图像使用POCOman软件进行分析,得出PCO的POCOman半客观评分.于Nd:YAG激光后囊切开术前、术后分别测量其最佳矫正视力(best corrected visual acuity,BCVA),同时使用自动眩光对比敏感度检查仪进行对比敏感度(contrast sensitivity,CS)和眩光对比敏感度(glare sensitivity,GS)的检测.分析统计不同类型、不同部位、不同程度PCO与视功能的关系.结果 珍珠型PCO在中心视力、各频段对比敏感度和眩光敏感度均低于纤维型PCO,且两者之间的差异有统计学意义(P<0.05);中央4.0mm珍珠型PCO在低、中频段对比敏感度和中频段眩光敏感度均低于中央2.0mm珍珠型PCO,差异有统计学意义(P<0.05).中央2.0mm纤维型PCO在中、高频段对比敏感度和低、中频眩光敏感度均低于中央4.0mm纤维型PCO,差异有统计学意义(P<0.05).中央2.0mm珍珠型PCO对最佳矫正视力的影响最为显著;中央4.0mm珍珠型PCO对对比敏感度和眩光敏感度的影响最为显著.随着PCO程度的增加,中心视力、全频段对比敏感度和全频段眩光敏感度逐渐下降.其间的差异有统计学意义.POCOman评分与最佳矫正视力、各频段对比敏感度、低中频段眩光敏感度的变化呈正相关(P<0.05),差异有统计学意义.结论 对后发性白内障行形态学及其对视功能受损的客观综合评价,可成为判断Nd:YAG激光晶状体后囊膜切开术手术时机和评价手术疗效的方法.     

Square-edge polymethylmethacrylate intraocular lens design for reducing posterior capsule opacification following paediatric cataract surgery: initial experience

Purpose: To compare the incidence and severity of development of posterior capsule opacification (PCO) following implantation of square‐edged polymethylmethacrylate (PMMA) or hydrophobic acrylic intraocular lenses (IOLs) following paediatric cataract surgery. Design: Prospective, consecutive, interventional, comparative, randomized and cross‐sectional study of 40 eyes of 32 children aged between 4 and 12 years who underwent phacoemulsification and posterior chamber IOL implantation. Methods: The patients were randomized into two groups of 20 eyes each. Group 1 eyes received a square‐edge hydrophobic acrylic IOL (Acrysof SA 60 AT, Alcon Surgical, Fort Worth, Texas), and Group 2 eyes received a square‐edge single‐piece PMMA lens (Aurolab SQ 3600 Aurolab IOL Division, Madurai, India) in the capsular bag. No eye underwent a primary posterior capsulotomy. The PCO density was evaluated on slitlamp retroillumination photographs by using POCOman software at 3, 6, 9 and 12 months post surgery. Results: The average percentage PCO on POCOman analysis was 51.23 for Group 1 and 49.49 for Group 2 (P = 0.09), and the average PCO severity grade was 1.34 in Group 1 and 1.12 in Group 2 (P = 0.08). Visual axis remained clear in 14 of 20 eyes with the acrylic lens as compared with 13 of 20 eyes with the PMMA lens. (P = 0.32). Conclusions: Square‐edge PMMA IOLs offer a significant cost advantage over acrylic lenses at similar rates of PCO formation following paediatric cataract surgery, which is of significant value in developing countries.     

Comparison of posterior capsule opacification rates between hydrophilic and hydrophobic single-piece acrylic intraocular lenses

PURPOSE: To determine the effect of intraocular lens (IOL) material on the development of posterior capsule opacification (PCO) at 1 year. SETTING: Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom. METHODS: One hundred six eyes of 53 patients with bilateral cataract and no other ocular comorbidity were prospectively randomized to receive a hydrophobic acrylic or hydrophilic acrylic single-piece IOL in the first eye to have surgery. The alternate IOL was implanted in the fellow eye 4 to 6 weeks later. All surgery was performed by a single surgeon. Postoperative follow-up was 1 day, 1 and 6 months, and 1 year. At each visit, the best corrected high- and low-contrast visual acuities were assessed and a high-intensity digital retroillumination photograph was taken. Posterior capsule opacification was assessed from the digital images by a single operator using a dedicated software program and calculated as the percentage area of opacified capsule. RESULTS: One year postoperatively, the median percentage area of PCO was 50.3% in the hydrophilic IOL group and 4.9% in the hydrophobic IOL group (P<.001). The difference in PCO was not accounted for by loss of contact between the capsulorhexis and IOL surface. Further analysis showed that lens epithelial cells tended to invade the posterior capsule at the haptic-optic junction. This was more marked in the hydrophilic IOL group. CONCLUSIONS: The rate of PCO was significantly higher with the hydrophilic IOL. However, the results cannot be attributed to the IOL material alone as they show the importance of both IOL material and design.     

Effect of cortical cleaving hydrodissection on posterior capsule opacification in age-related nuclear cataract

PURPOSE: To evaluate the effect of multiquadrant cortical cleaving hydrodissection on the development of posterior capsule opacification (PCO) after phacoemulsification. SETTING: Iladevi Cataract and IOL Research Center, Ahmedabad, India. METHODS: A prospective randomized triple blind clinical trial was conducted in 86 eyes (86 patients) having phacoemulsification. Eyes were assigned randomly to Group 1, multiquadrant cortical cleaving hydrodissection and hydrodelineation (n = 48 eyes), or Group 2, no multiquadrant cortical cleaving hydrodissection, only hydrodelineation (n = 38 eyes). Age-related nuclear sclerosis (grading system of 1 to 5) and age greater than 50 years were included. Diabetes mellitus and associated eye diseases were excluded. Standard phacoemulsification with implantation of an AcrySof MA30BA intraocular lens (IOL) was done in both groups. High-resolution digital retroillumination images of the posterior capsule were analyzed at 4 years using POCOman software. Seven patients dropped out (8.1%). Outcome measures were incidence and percentage area of PCO. Test of proportions, independent sample t test, and 95% confidence intervals (CIs) were noted. RESULTS: In Groups 1 and 2, the mean age was 58 years +/- 4 (SD) and 57 +/- 5 years, respectively (P = .702; 95% CI, 1.90-2.81); mean follow-up was 48.4 +/- 2.5 months and 49.3 +/- 1.9 months, respectively (P = .687; 95% CI, 1.186-0.7856); incidence of PCO was 11 of 44 (25%) and 12 of 35 (34.3%), respectively (P = .317; 95% CI, 0.359-0.0889); percentage area of PCO was 14.3% and 25.6%, respectively (P = .006; 95% CI, -19.19 to -3.44). One of 44 eyes (2.27%) and 2 of 35 eyes (5.7%) in the groups, respectively, had a neodymium:YAG capsulotomy. CONCLUSION: Although no difference was noted in the incidence of PCO, in eyes that had PCO, the percentage of the area of the central posterior capsule involved by PCO was significantly lower in eyes that had multiquadrant cortical cleaving hydrodissection than in those that did not.     

Reproducibility of standardized retroillumination photography for quantification of posterior capsule opacification

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.     

Long-term effect of optic edge design in a silicone intraocular lens on posterior capsule opacification

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.     

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.     

Evaluation of posterior capsule opacification using a new posterior view method in rabbits: single-piece acrylic versus 3-piece acrylic intraocular lens

PURPOSE: To introduce a new procedure for evaluating posterior capsule opacification (PCO) in rabbit eyes and to perform a comparative study of the single-piece and 3-piece acrylic intraocular lenses (IOLs) on PCO using the new evaluation method. SETTING: Jinshikai Medical Foundation, Nishi Eye Hospital, Osaka, Japan. METHODS: A single-piece or 3-piece acrylic IOL was implanted in 1 eye and the other in the contralateral eye of 5 rabbits. Three weeks after surgery, PCO was scored by Evaluation of Posterior Capsule Opacification (EPCO) in posterior view. Before the posterior view was photographed, the anterior capsule was removed from the whole optic area to eliminate disturbing anterior capsule opacification (ACO) for the PCO evaluation. RESULTS: Posterior capsule opacification could be well observed and viewed in the posterior view so that it could be scored by EPCO without confusion with ACO. The mean PCO score of the single-piece and 3-piece acrylic IOLs was 3.12 +/- 0.19 and 2.41 +/- 0.70, respectively (P < .05 and P = .03, respectively). CONCLUSION: The removal of ACO allowed scoring of PCO by EPCO in rabbit eyes. The single-piece acrylic IOL showed significantly more PCO than the 3-piece acrylic IOL at least 3 weeks after surgery in rabbits.