retinopathy

any of various disorders of the retina resulting in impairment or loss of vision. It is usually due to damage to the blood vessels of the retina, occurring (for example) as a complication of longstanding diabetes ( diabetic retinopathy), high blood pressure, or AIDS (AIDS retinopathy). In diabetic retinopathy, haemorrhaging or exudation may occur, either from damaged vessels into the retina or from new abnormal vessels ( see neovascularization ) into the vitreous humour. Treatment of the later stages requires laser surgery (see photocoagulation ). Diabetic retinopathy can be detected by careful eye examination before it causes a deterioration in vision.