Symptoms of amaurosis fugax in atherosclerotic carotid artery disease.

Amaurosis fugax is a term used to describe transient monocular visual loss due to atherosclerosis of the ipsilateral internal carotid artery. It is differentiated from other causes of transient monocular blindness, especially retinal migraine. It is said that amaurosis fugax episodes are short in duration and only occasionally include "positive" visual phenomena such as scintillations. Monocular migraine is more prolonged and often accompanied by scintillations. We studied 37 patients with amaurosis fugax and angiographic evidence of carotid atherosclerosis ipsilateral to the symptomatic eye. Nearly one-third of the patients had long attacks or positive visual phenomena. In many patients, transient monocular visual loss due to carotid atherosclerosis cannot be differentiated from retinal migraine based on clinical symptoms alone.