Histopathology of argon laser photocoagulation in juvenile diabetic retinopathy

A 24-year-old woman had insulin-dependent juvenile diabetes for 15 years. She developed Sheehan's syndrome (postpartum pituitary necrosis) and diabetic nephropathy at 20 years of age. She had multiple sessions of argon laser photocoagulation for proliferative diabetic retinopathy. Histologically, loss of outer retina and pigmented epithelium occurred at the laser sites. Trypsin retinal digest preparations revealed microaneurysms and markedly decreased numbers of pericytes. The kidneys displayed nodular glomerulosclerosis (Kimmelstiel-Wilson syndrome). The anterior pituitary showed cystic degeneration and old hemorrhage.