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Retinal artery occlusion (CRAO and BRAO)
Central retinal artery occlusion is a stroke of the eye — sudden, painless, profound loss of vision with a white retina and a cherry-red spot — so it is managed like a stroke: immediate referral to a stroke centre, a search for an embolic source and exclusion of giant cell arteritis in older patients.
Why it matters in the exam
In the exam: an older adult with hypertension, diabetes or atrial fibrillation loses vision in one eye all at once, sometimes after episodes of transient visual loss (amaurosis fugax). On examination: counting fingers or worse, a marked RAPD, a white oedematous retina with a cherry-red spot at the centre (the choroid seen through the thin fovea), narrow arteries and sometimes segmented flow (box-carring). About 15–30% of people have a cilioretinal artery that supplies the macula and preserves central vision.
After CRAO the risk of cerebral stroke is particularly high in the first weeks, so the 2021 AHA statement recommends immediate referral to a stroke centre with brain imaging, carotid duplex, ECG and rhythm monitoring, echocardiography and blood tests. In a patient over 50 GCA must be excluded — ask about headache, scalp tenderness, jaw claudication and weight loss, and check ESR and CRP; if suspicion is reasonable — steroids at once, before biopsy.
The "conservative" treatments — ocular massage, anterior chamber paracentesis, acetazolamide and carbogen breathing — have not been shown to work. Intravenous thrombolysis within a short time window (up to 4.5 hours) is being studied and considered in stroke centres. The retina tolerates ischaemia only briefly, so every minute matters. Even after the acute event the eye needs follow-up, because iris new vessels can appear in the weeks after the occlusion. In BRAO the embolus is sometimes visible: Hollenhorst — cholesterol from the carotid, bright and refractile at a bifurcation; fibrin-platelet — white and elongated; calcific — from a valve, chalky white.
Key points
- Sudden, painless, profound loss of vision, RAPD.
- White retina and a cherry-red spot.
- Stroke of the eye → stroke centre at once.
- Over 50 — exclude GCA.
- Conservative treatments unproven; thrombolysis under study.
Summary table
| Finding | What it means | What to do |
|---|---|---|
| Cherry-red spot and white retina | CRAO | Stroke centre at once, embolic work-up |
| Preserved central vision | Cilioretinal artery | Same work-up; better prognosis |
| Over 50 with headache and jaw claudication | GCA | ESR and CRP, steroids at once, biopsy |
| Hollenhorst embolus | Cholesterol from the carotid | Carotid duplex |
| Amaurosis fugax | Retinal TIA | Same urgent work-up as TIA |
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Sources
- AAO Preferred Practice Pattern: Retinal and Ophthalmic Artery Occlusions, 2019 — Evaluation and management
- American Heart Association Scientific Statement: Management of Central Retinal Artery Occlusion, 2021 — Acute evaluation and secondary prevention
- AAO Basic and Clinical Science Course, Section 12: Retina and Vitreous, 2024-2025 — Retinal arterial occlusive disease
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.