Half-life of cotton-wool spots in the acquired immunodeficiency syndrome.

Cotton-wool spots are a hallmark of human immunodeficiency virus (HIV) retinopathy in the acquired immunodeficiency syndrome (AIDS). We analysed the half-life of cotton-wool spots in AIDS in a prospective study, and found the average time to disappearance to be 6.9 weeks. HIV retinopathy differs from diabetic retinopathy in having a smaller size cotton-wool spot and a much shorter half-life, suggesting a patchy involvement of the retinal capillaries in AIDS and a widespread capillary disease in preproliferative and proliferative diabetic retinopathy.