Postoperative membranous proliferation outgrowth onto the anterior surface of hydrophobic acrylic intraocular lenses

Purpose: The aim of this study was to determine the correlation factors and features of membranous outgrowth onto the anterior surface of hydrophobic acrylic intraocular lenses. Methods: This study included 145 eyes from 135 consecutive patients who had cataract surgery with implantation of a single-piece, foldable, hydrophobic acrylic intraocular lens. Postoperatively, the IOL optic was examined by slit-lamp microscopy at 1 week and1 month to determine the incidence, extent, and correlation factors of membranous proliferation. If MP was present, we re-examined the patient monthly to monitor the condition. The extent of this proliferation was assessed using a clock-face representation of the IOL optic as the number of hours in which membranous proliferation could be identified. Results: Twenty-four eyes were excluded from analysis and 121 remaining eyes were studied. Membranous proliferation was documented in 46 (38.02%) of the pseudophakic eyes. Furthermore, the incidence of membranous outgrowth was greater in pseudophakic eyes characterized by older age, shorter axial length and more serious anterior segment vitreous opacity. Membranous proliferation was greater in the inferior (35.11%) and nasal quadrants (33.51%) than in the superior and temporal quadrants (where the incisions were made). The total area of membranous proliferation was slightly less than one quadrant (56.52%). Conclusions: Shorter axial length, older age, serious anterior segment vitreous opacity, and the inferior and nasal quadrants are risk factors for membranous proliferation on the IOL surface. Appreciation of these risk factors may lead to establishing procedures that will lessen anterior capsule opacification and capsule contraction syndrome simultaneously.