Effect of silicone oil on ocular tissues.

The effect of silicone oil on ocular tissues was investigated histopathologically in rabbit eyes by injecting silicone oil into the anterior chamber or the vitreous cavity after vitrectomy. The eyes were enucleated 3, 6, 9, 12 or 18 months after the injection and various tissues were observed by light and electron microscopy. Silicone oil was first observed in the retrocorneal membrane at 18 months after the injection. In the trabecular meshwork silicone oil was seen for the first time at 12 months after injection. Migrating cells engulfing silicone oil attached to the internal limiting membrane of the retina 3 months after the injection. Twelve and 18 months after the injection, silicone oil passed through the internal limiting membrane and was engulfed by Müller cells. These results indicate that attention should be paid to the effects of silicone oil on ocular tissues when it remains in the eye for a long time since, after a certain period, cells of the trabecular meshwork and retina may engulf silicone oil.