Effect of in-the-bag intraocular lens fixation on the prevention of posterior capsule opacification

Purpose: To compare the incidence of posterior capsule opacification (PCO) after extracapsular cataract extraction (ECCE) and phacoemulsification and to evaluate the role of posterior chamber intraocular lens (PC IOL) haptic fixation and biomaterial/design in reducing the incidence. Setting: Postgraduate Institute of Medical Education and Research, Chandiga rh, India; Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Car olina, USA. Methods. This study comprised 278 eyes of 263 patients having ECCE and 318 eyes of 297 patients having phacoemulsification with PC IOL implantation. P osterior capsule opacification leading to a decrease in Snellen visual acui ty of 2 or more lines was considered visually significant. The presence of PCO and IOL haptic fixation were evaluated postoperatively using slitlamp b iomicroscopy. Haptic position was noted as in-the-bag (B-B), 1 haptic in th e bag and 1 in the sulcus (bag-sulcus [B-S]), or both haptics out of the ba g (sulcus-sulcus [S-S]). In addition, the rate of visually significant PCO was compared among 3 IOL biomaterials: poly(methyl methacrylate), silicone, and hydrophobic acrylic. Results: Visually significant PCO occurred in 42.45% of eyes having ECCE an d 19.18% of eyes having phacoemulsification (P < .001, chi-square test) aft er a mean follow-up of 2.4 years +/- 0.7 (SID). In both groups, visually si gnificant PCO was significantly less in eyes with B-B fixation than in thos e with B-S or S-S fixation (P < .001). The rate of visually significant PCO in all eyes in the phacoemulsification group with B-B fixation was low (11 .90%) and was significantly lower in eyes with a hydrophobic acrylic IOL (2 .22%; P < .05, chi-square test). Conclusions. In-the-bag PC IOL fixation is required to consistently reduce the incidence of PCO. Thorough removal of lens substance, including hydrodi ssection-assisted cortical cleanup, and in-the-bag PC IOL fixation seem to be the most important factors in reducing PCO, regardless of surgical proce dure or IOL type used. Intraocular lens biomaterial and design also help pr event PCO. (C) 2001 ASCRS and ESCRS.