Square edge PMMA 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.