Effect of anterior capsule polishing on capsule opacification and YAG laser capsulotomy

Abstract

Lens epithelial cells (LECs) at the rhexis edge and in the area surrounding the optic (A-LECs) are the main cause not only for fibrotic whitening and contraction of the capsule but also for permanent collagenous sealing of the capsule bag following intraocular lens (IOL) implantation. Anterior capsule polishing (ACP) mainly removes these A-LECs. Methods differ in efficiency of LEC removal and in the trauma thereby exerted on capsule, zonules and ciliary body. Even after thorough removal, fibrosis does partly occur. Regarding the impact on regeneratory posterior capsule opacification (PCO) formation, no increase in PCO rates was found when evaluating retroilluminated photographs. In spite of this, a considerable increase in YAG laser capsulotomy rate was found by one study group. As the cause, accumulation of amorphous LEC material was detected in the retrolental space. Bending and collagenous bonding of the capsules which provide for a lasting barrier effect at the optic circumference was found to be compromised. Thus, ACP though decreasing capsular whitening and shrinkage apparently interferes with barrier formation. ACP also changes the morphology of LECs accumulating in the retrolental space, causing a decrease of contrast vision while not picked up upon retroillumination. Thus, ACP is not recommended with standard in-the-bag IOL implantation. ACP is a useful adjunct to the posterior optic buttonholing technique where retrolental LEC invasion is independent from capsule bending and thus cannot be affected. The impact of ACP on capsular bag closure and cellular reaction as visualized by biomicroscopy elucidates the physiology of after-cataract formation and the mechanism of barrier formation at the IOL optic barrier.