AKT · Ophthalmology/Retina & vitreous

Central retinal artery occlusion

Embolic/thrombotic occlusion of the central retinal artery (a retinal 'stroke')

Overview

Sudden, painless, profound monocular visual loss from occlusion of the central retinal artery — effectively a retinal stroke. Causes: carotid/cardiac embolism, and crucially giant cell arteritis. Fundus shows a pale retina with a cherry-red spot and an RAPD. Time-critical, with a poor prognosis; treat as a stroke/TIA equivalent and exclude GCA.

Recognise

Sudden, painless, severe LOSS of vision in one eye (often counting-fingers or worse)
Relative afferent pupillary defect (RAPD); fundus: pale oedematous retina with a CHERRY-RED SPOT at the macula; segmented 'cattle-trucking' in vessels
Amaurosis fugax (transient curtain) may precede it; embolic source (carotid, AF) or GCA

Red flags

CRAO is a stroke equivalent → urgent stroke pathway (carotid imaging, ECG, vascular risk) AND exclude GCA (ESR/CRP) in the older patient — bilateral blindness risk
Jaw claudication, scalp tenderness, headache → arteritic cause: high-dose steroids immediately

Differentials & how to tell them apart

Central retinal vein occlusionless severe loss; fundus of widespread haemorrhages ('stormy sunset'), not a pale cherry-red-spot retina

Arteritic AION (GCA)swollen pale disc; the must-exclude cause — check ESR/CRP

Retinal detachmentcurtain/field defect with flashes/floaters, not a sudden total whiteout with a cherry-red spot

Vitreous haemorrhagesudden floaters/haze with loss of the red reflex, often diabetic

CRAO — pale retina with a cherry-red spot at the macula
Dr. Gopal Bisht / CC BY-SA 4.0 — Wikimedia Commons

Investigations

Urgent ESR/CRP (exclude GCA), fundoscopy, carotid Doppler, ECG/echo for embolic source; same as TIA work-up.

Management

Emergency referral; exclude GCA (steroids if arteritic) + stroke-pathway work-up

1Emergency ophthalmology/stroke assessment. Acute ocular-massage / IOP-lowering (acetazolamide, anterior-chamber paracentesis) are sometimes attempted within hours but evidence is limited.Gate: In anyone ≥50, CHECK ESR/CRP and treat as GCA with high-dose steroids if suspected BEFORE the fellow eye is lost; otherwise manage as a TIA/stroke equivalent (carotid imaging, ECG, vascular prevention)
2Vascular secondary prevention (antiplatelet, statin, BP/AF management); carotid endarterectomy for significant ipsilateral stenosis.

High-dose corticosteroid — IMMEDIATELY if GCA suspected (oral/IV) to protect the fellow eye

Antiplatelet + vascular secondary prevention — embolic cause — statin, BP, AF management (as for stroke/TIA)

Key points

Sudden painless monocular blindness + RAPD + cherry-red spot = CRAO. It is a stroke — work it up as one, and never miss GCA in the older patient.

Monitor & prognosis

Vascular risk-factor management; GCA follow-up if arteritic.

Poor visual recovery; the priority is the brain and the fellow eye.

Source: RCOphth; cross-ref neurology (stroke/GCA)