Hemorrhage from isolated aneurysm of a retinal artery: report of two cases simulating malignant melanoma.

Isolated retinal arterial aneurysms or macroaneurysms of the retinal arteries may be the cause of hemorrhage in the retina or vitreous. Two cases are reported in which hemorrhages from isolated retinal arterial aneurysms clinically simulated malignant melanoma of the choroid. Previous studies of lesions simulating malignant melanoma of the uvea have shown that vitreous and retinal hemorrhage may easily mislead the clinician. It is stressed that careful prolonged observation does not materially decrease the patient's chance for survival if he does have a malignant melanoma and may prevent an unnecessary enucleation.