CMV retinitis in AIDS. Ophthalmoscope view of the retina of an AIDS patient, showing the damage resulting from cytomegalovirus (CMV) infection. The virus causes inflammation of the blood vessels (vasculitis), leading to areas of infarction (dark patches, at lower right) in which cell death results from a cessation of blood supply. White cotton wool areas represent deposition of fatty exudates as well as reduced blood flow. CMV retinitis is the most common eye disorder in AIDS (Acquired Immune Deficiency Syndrome); it may progress rapidly to irreversible blindness. Treatment may include the use of antiviral drugs such as acyclovir.