Morphological Changes in Patient Lens Epithelial Cells after Intravitreal Silicone Oil Injection

The subject patient (47-year-old male) had received silicone oil injection into the vitreous cavity of his left eye for the treatment of retinal detachment in 1986. Two months later, the silicone oil was removed from the vitreous cavity, as the retina was reattached. Soon after the operation, the lens of the eye gradually became opaque to mature cataract, and his left visual acuity had fallen to hand motion upon his present admission to the hospital. The lens epithelium obtained by anterior capsulotomy during the extracapsular cataract extraction was examined morphologically by transmission electron microscopy. Inside the anterior lens capsule, abnormal epithelial proliferation was observed. The epithelial cells changed their shapes from cuboidal to spindle, accompanied by new basal lamina-like substances around them. The spindle-shaped cells stretched like pseudopodia. The extracellular matrices were abundant and composed of collagen fibers. Fragments and dissolved materials of the fibers were also seen in some specimens. Lipid-like substances and myelin-like structures were often observed in the relatively well preserved cytoplasm. As a result, it is surmised that cataract formation after intravitreal silicone oil injection may be associated with fibrous pseudometaplasia of the lens epithelial cells and phagocytosed silicone oil deposits in the epithelial cells.