[citation needed] Prior to 1990, amaurosis fugax could, "clinically, be divided into four identifiable symptom complexes, each with its underlying pathoetiology: embolic, hypoperfusion, angiospasm, and unknown".

If the patient has no history of giant cell arteritis, the probability of vision preservation is high; however, the chance of a stroke reaches that for a hemispheric TIA.

[8] A diagnostic evaluation should begin with the patient's history, followed by a physical exam, with particular importance being paid to the ophthalmic examination with regards to signs of ocular ischemia.

However, in the event that both of these routes of investigation yield normal findings or an inadequate explanation, non-invasive duplex ultrasound studies are recommended to identify carotid artery disease.

However, carotid angiography may not be necessary in the presence of a normal ultrasound and CT.[42] Fleeting loss of vision does not in itself require any treatment, but it may indicate an underlying condition, sometimes serious, that must be treated.

If the amaurosis fugax is caused by an atherosclerotic lesion, use of aspirin as an anticoagulant is indicated, and a carotid endarterectomy considered based on the location and grade of the stenosis.

"[43] However, the rate of subsequent stroke after amaurosis is significantly less than after a hemispheric TIA, therefore there remains debate as to the precise indications for which a carotid endarterectomy should be performed.