Effect of cataract surgery and intraocular lenses on diabetic retinopathy.

We reviewed a series of 137 cataract extractions with intraocular lenses (IOLs) in patients with diabetes, mellitus between 1977 and 1983. All patients were followed for an average of 36 months to determine if they subsequently showed progression of diabetic retinopathy. Divided into groups according to the type of procedure and IOL received, they were compared for age, sex, duration of diabetes, treatment required for the diabetes, intraoperative complications, and follow-up period. Patients who had intracapsular cataract extractions with anterior chamber IOLs were three times as likely to show proliferative retinopathy as those who had extracapsular cataract extractions with posterior chamber IOLs. Insulin-dependent patients were three to four times more likely to show progression to proliferation than noninsulin dependent patients. We conclude that, while some procedures are riskier for the diabetic eye, extracapsular lens extraction with implantation of a posterior chamber lens does not imply an increased risk of development of proliferative retinopathy.