Diabetic Retinopathy

IT is estimated that 5000 patients with diabetes in the United States and 30,000 to 40,000 worldwide become blind each year from retinopathy. Despite advances in the use of photocoagulation and vitrectomy, diabetic retinopathy has been the leading cause of blindness in Great Britain, North America, Europe, and Scandinavia since 1974.1 The sequence of anatomical changes in the retina leading to blindness in diabetes is fairly well defined,2 3 4 but the causes are poorly understood. Most components of diabetic retinopathy, including endothelial proliferation, capillary closure, and preretinal neovascularization, occur in other diseases. However, the constellation of lesions, from early thickening of . . .