Lens epithelial cell regression on the posterior capsule with different intraocular lens materials

Abstract

Background/aims-Posterior capsular opacification (PCO) is caused by proliferation and migration of lens epithelial cells (LECs) across the posterior capsule and is the commonest cause of reduced vision after cataract surgery. The influence of intraocular lens (IOL) material on the process of LEC migration was studied. Methods-90 eyes underwent standardised extracapsular surgery, with capsulorhexis and "in the bag" IOL placement. They were randomised to receive a three piece 6 mm lens of PMMA, silicone, or polyacrylic (AcrySof, Alcon, Fort Worth, TX, USA). On days 7, 30, 90, 180, and years 1 and 2 high resolution digitised retroillumination images were taken of the posterior capsule. The presence of LECs was determined at 90 days and 2 years, and their progression or regression was established by serial examination of images. Results-LECs were seen in 93% of silicone and 97% of PMMA IOLs at 90 days, compared with 46% of polyacrylic (p<0.001). At year 2 LECs were present in all patients with silicone or PMMA lenses, whereas 62% of patients with polyacrylic IOLs had LECs (p<0.001). Of those patients with LECs at day 90 LEC regression occurred in 8% with silicone IOLs and 15% of PMMA cases, compared with 83% of patients with polyacrylic IOLs (p<0.0001). Conclusion-The presence of LECs on the posterior capsule was considerably lower with polyacrylic than PMMA or silicone IOLs and LEC regression occurred more frequently. The lower incidence of LECs and the higher rate of regression may explain why PCO formation appears to be reduced with polyacrylic lenses. This has important clinical implications for the prevention of PCO. (Br J Ophthalmol 1998;82:1182-1188 Posterior capsular opacification (PCO) is the commonest complication of cataract surgery with an incidence of between 10% and 50% by 2 years postoperatively.

Complications of cataract surgery

“…A considerable volume of clinical research shows that a square IOL edge inhibits lens epithelial cell migration to the posterior capsule. [17][18][19] In the event of the development of postoperative posterior capsular opacification, the treatment is a capsulotomy using an …”

Avaliação histopatológica da cápsula posterior associada ao implante de lente intraocular com superfície modificada com plasma de flúor e polietilenoglicol em coelhos

“…Esses coelhos possuíam o implante LIO, e tal fato pode ser explicado pela associação do tratamento instituído nas LIOs, mas também pela própria presença da LIO, uma vez que ela pode exercer um efeito barreira, impedindo a exposição das CELs ao humor aquoso que é rico em fator transformador β, responsável pela transição epitelial-mesenquimal das CELs (Shirai et al, 2004;Wedje et al, 2004). Salienta-se ainda que esse efeito barreira impede o acesso de nutrientes e fatores de crescimento, resultando na regressão e atrofia das CELs que migraram para cápsula posterior (Hollick et al, 1998).…”

Optical Coherence Tomography of Intraocular Lens Implants and Their Relationship to the Posterior Capsule: A Pilot Study Comparing a Hydrophobic Acrylic to a Plate-Haptic Silicone Type

“…In a study by Hollick et al [19] , LECs that migrated behind the hydrophobic acrylic (Acrysof) IOL optic were found to disappear. Our fi nding that the central optically empty space between the implant and the posterior capsule disappeared within few weeks postoperatively corroborates the authors' hypothesis that related that phenomenon to mechanical compression exerted on the cells by the optic of the implant.…”