DECENTRATION ASSOCIATED WITH ASYMMETRIC CAPSULAR SHRINKAGE AND INTRAOCULAR-LENS DESIGN IN A RABBIT MODEL

We evaluated intraocular lens (IOL) decentration resulting from asymme tric capsular shrinkage. In 19 eyes of 10 white rabbits, a D-shaped in cision was made in the anterior capsule and one of three IOL types imp lanted in the capsular bag: three-piece with polypropylene haptics, on e-piece all-poly(methyl methacrylate) (PMMA), or compressible disk. Ei ght weeks later, eyes were enucleated for assessment of IOL decentrati on. Mean decentration was 0.75 mm for three-piece IOLs, 0.46 mm for on e-piece IOLs, and 0.30 mm for compressible-disk lenses. Decentration w as significantly less in eyes with compressible-disk lenses than in th ose with three-piece IOLs. Although decentration was less with the com pressible-disk lens, the lens is not commonly used because of the larg e incision and special insertion technique required. If an open-loop I OL is to be used in eyes at risk for asymmetric capsular shrinkage, ou r results indicate that an all-PMMA one-piece IOL would be preferable to a three-piece lens with a polypropylene haptic.