Amaurosis fugax is the transient monocular loss of vision, normally lasting a few seconds to a few minutes, secondary to vascular ischaemia or insufficiency.
It has an incidence of 50,000 per year in the United States.
Patients present with transient monocular, painless, loss of vision lasting seconds to minutes, with full resolution.
Common aetiologies include:
- hypoperfusion secondary to increased metabolic demands on a background of severe atherosclerotic vessels or acute hypovolaemia
- retinal arterial- or vaso-spasm (e.g. giant cell arteritis)
- ocular vascular disease
- neurological (e.g. optic neuritis)
Although different aetiologies will have different radiographic features, a work-up of a patient presenting with amaurosis fugax may include:
- Duplex ultrasound of carotid arteries
- identifying occulsion, stenosis and ulcerations at the bifurcation
- consider CTA or MRA
- echocardiogram to identify cardio-embolic causes
Treatment and prognosis
Management depends on the underlying cause. During the work-up, modifiable risk factors should be addressed (e.g. smoking cessation, control of diabetes, control of hyperlipidemia) and patients may be commenced on aspirin for stroke prevention (the annual incidence of stroke in patients with amaurosis fugax is 2%).
- multiple sclerosis
- anterior ischaemic optic neuropathy (AION)
- central or branch retinal artery occlusion (CRAO/BRAO)
- central retinal vein occulsion (CRVO)
- acute angle-closure glaucoma
- prevention of stroke is key from this presentation
- 1. Maguire J, Murchison A, Jaeger E. (2012). Wills Eye Institute 5-minute ophthalmology consult. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, pp.72-73.
- 2. Current management of amaurosis fugax. The Amaurosis Fugax Study Group. (1990) Stroke. 21 (2): 201-8. Pubmed