SEP 16, 2008
Cataract/Anterior Segment
This prospective randomized intraindividual trial found that capsular bending ring (CBR) implantation, used as an adjunct to in-the-bag IOL fixation, led to a significant reduction in regeneratory posterior capsular opacification (PCO) and fibrotic anterior capsule opacification over a three-year period.
However, the authors found that CBR use did not completely prevent PCO formation and recommended strategies for optimizing CBR performance, including the production of a CBR with very sharp edges and an open-ring design.
Sixty patients with bilateral cataract requiring surgery served as subjects in the study. They were all implanted with the Bausch & Lomb Hydroview H60M IOL in both eyes and a 0.7-mm high open poly(methyl methacrylate) (PMMA) CBR in one eye.
The objective PCO score and area were significantly lower in eyes implanted with a CBR compared to control eyes after one, two, and three years. Haptic-induced stress folds in the posterior capsule were significantly more common among the eyes without CBRs. Fibrotic anterior opacification was significantly less in the eyes with CBRs. The authors reported no CBR-related surgical complications.
They suggested additional CBR strategies, including:
- Making the capsulorhexis as large as possible
- Using a CBR that provides for full circumferential capsular bending independent of varying capsular bag diameter
- Using IOLs with CBRs that have an anterior-convex posterior-plano optic and anteriorly angulated loops with permanent memory in order to prevent peripheral retro-optical interspacing and pearl ingrowth.