Calcification on posterior surface of implanted silicone intraocular lens.

Abstract

Abstract: : Purpose:Although calcification on the surface of hydrogel intraocular lenses (IOL) is well known, the mechanism of the calcification is not fully understood. We report the first case of calcification in an implanted silicone IOL. The purpose of our study was to determine the clinical and ultrastructural findings of the late calcification of a silicone IOL explanted from a patient with late postoperative visual disturbance. Methods:A 70–year–old Japanese male patient without any systemic or ocular associated pathology presented with blurred, glare–sensitive, decreased vision 29 mo. after uneventful phacoemulsification and silicone IOL (Allergan SI–55NB) implantation with manufacturer’s cartridge and injector. Although YAG laser capsulotomy was performed, a layer of irregular opacity gradually developed. The opacity was located mainly within the capsulotomy window on the posterior surface of the lens. The lens was removed 46 mo. after the initial surgery, and was submitted for examination by light microscopy, scanning electron microscopy (SEM), and energy–dispersive x–ray spectroscopy (EDS). Results:The opacity was located on the posterior surface of the IOL, and light microscopy and SEM revealed the presence of irregular, amorphous membranous deposits on the posterior optical surface of the silicone lens, which was different from the granular nature of hydrogel IOL calcifications. The deposits were detached by tight compression with forceps, and EDS demonstrated the presence of calcium and phosphates within the deposits. Conclusions: This is the first report of calcification on a silicone IOL. Although the mechanism of the calcification was not determined, careful clinical follow–up of patients implanted with silicone lenses is necessary to determine if this phenomenon is rare and sporadic or may be more widespread.

Keywords: small incision cataract surgery • cataract • clinical (human) or epidemiologic studies: outcomes/complications