Amaurosis fugax is a sudden, painless, temporary loss of vision in one eye, usually lasting minutes, caused by a short drop in blood flow to the retina. It is a transient ischemic attack of the eye and a warning sign of stroke, often from carotid artery disease.
Key symptoms
- Sudden painless vision loss in one eye
- Often described as a curtain or shade coming down
- Full recovery within seconds to minutes
- Sometimes weakness, numbness or speech trouble at the same time
What you find on exam
- Visual acuity and visual fields, often normal after the episode
- Fundoscopy: bright emboli in the retinal arteries (Hollenhorst plaques)
- Carotid bruit and irregular pulse
- Full neurological exam
- Temporal artery tenderness in older patients
Tests
- Urgent carotid ultrasound or CT angiography
- Brain MRI with diffusion imaging
- ECG and heart monitoring for atrial fibrillation; echocardiogram
- Lipids, glucose, HbA1c; ESR and CRP if over 50 (giant cell arteritis)
Treatment basics
- Treat as a TIA: same-day stroke work-up
- Antiplatelet therapy such as aspirin and a high-intensity statin such as atorvastatin
- Carotid endarterectomy or stenting for significant narrowing on the same side
- Anticoagulation if atrial fibrillation is found
- Control blood pressure, diabetes and smoking
Red flags
- Vision loss that does not recover (possible retinal artery occlusion)
- New weakness, facial droop or speech trouble
- Headache, jaw pain with chewing or scalp tenderness in an older patient
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.