Central Retinal Artery Occlusion — ED Actions

Key Points

• Treat acute CRAO as an ocular ischemic stroke and send the patient immediately to a stroke-capable center.
• Document last-known-well time because potential reperfusion decisions are time dependent.
• Do not delay stroke evaluation for unproven ocular maneuvers such as routine ocular massage.
• A normal early fundus appearance does not exclude CRAO when the clinical presentation is convincing.
• Screen urgently for giant cell arteritis in the appropriate age and symptom group.
• Selected very early patients may be considered for IV thrombolysis under a coordinated stroke protocol.
• The systemic evaluation should search for carotid and cardiac embolic sources.
• Secondary stroke prevention is a core component of CRAO treatment even when vision does not recover.

Algorithm

1. Confirm sudden monocular vision loss and record exact onset or last-known-well time.
2. Perform visual acuity, pupils, confrontation fields, intraocular pressure, and focused funduscopic examination without delaying transfer.
3. Activate stroke-center evaluation and obtain ophthalmology input as rapidly as feasible.
4. Evaluate for giant cell arteritis with history, ESR, CRP, CBC/platelets, and immediate steroid pathway when suspected.
5. Obtain brain and vascular imaging, ECG/rhythm evaluation, and cardioembolic workup according to the stroke pathway.
6. Consider reperfusion therapy only through an established multidisciplinary protocol in an eligible early presenter.
7. Initiate mechanism-appropriate antithrombotic and vascular risk-reduction therapy after hemorrhage and contraindications are excluded.
8. Arrange ophthalmology, neurology, and primary-care follow-up for visual rehabilitation and secondary prevention.

Clinical Synopsis & Reasoning

CRAO classically presents as abrupt painless loss of vision in one eye, often described as a curtain, blackout, or severe central-field deficit. Visual acuity may range from counting fingers to no light perception depending on whether a cilioretinal artery preserves part of the macula. A relative afferent pupillary defect is typical when unilateral. Funduscopic findings can include retinal whitening and a cherry-red spot, but these changes may be subtle in the earliest minutes. Optical coherence tomography and specialist examination can support diagnosis without delaying stroke evaluation.

The pathophysiology is usually embolic or thrombotic interruption of retinal arterial flow, commonly related to carotid atherosclerosis or cardiac embolic sources. Because the retina is central nervous system tissue, symptomatic retinal artery occlusion is treated as an ischemic stroke equivalent. The 2024 American Academy of Ophthalmology Preferred Practice Pattern recommends immediate referral of acute symptomatic retinal or ophthalmic artery occlusion to the nearest stroke referral center. The evaluation therefore includes brain and vascular imaging, ECG and rhythm assessment, vascular risk factors, and cardiac evaluation similar to other transient ischemic or ischemic stroke presentations.

Always consider arteritic CRAO from giant cell arteritis in an older patient, particularly with new headache, scalp tenderness, jaw claudication, polymyalgia symptoms, constitutional symptoms, or elevated inflammatory markers. Arteritic disease threatens the fellow eye and requires immediate high-dose corticosteroid treatment after appropriate evaluation, not routine CRAO maneuvers. Other mimics include retinal detachment, vitreous hemorrhage, optic neuritis, nonarteritic ischemic optic neuropathy, acute angle closure, and occipital stroke.

Treatment Strategy & Disposition

Establish the exact time of onset or last known well immediately. There is no universally proven ocular maneuver that reliably restores vision. Historical interventions such as ocular massage, anterior chamber paracentesis, carbogen, or routine pressure-lowering therapy have not demonstrated consistent benefit and should not delay stroke-center transfer. Measure intraocular pressure and treat another ocular emergency if present, but the central treatment pathway is urgent vascular-neurologic assessment.

For patients presenting very early, some comprehensive stroke programs consider IV thrombolysis using an ischemic-stroke framework when the diagnosis is secure, the vision deficit is disabling, and standard thrombolytic contraindications are absent. Evidence remains less definitive than for cerebral ischemic stroke, so treatment should follow a local stroke-ophthalmology protocol rather than improvised ED use. Intra-arterial therapy is investigational or center-specific and is not standard routine management. Hyperbaric oxygen has been studied and may be considered at selected experienced centers, but availability and evidence vary.

Secondary prevention is essential because CRAO can herald cerebral stroke or myocardial infarction. Evaluate carotid disease, atrial fibrillation, hypertension, diabetes, dyslipidemia, smoking, and other vascular risks. Start antithrombotic and vascular-prevention therapy according to the determined mechanism and stroke recommendations. Patients with arteritic CRAO require immediate systemic steroid therapy and rheumatology or neuro-ophthalmology management to protect the fellow eye.

Epidemiology / Risk Factors

• CRAO is uncommon compared with cerebral ischemic stroke but shares many atherosclerotic and embolic risk factors.
• Incidence increases with age and vascular disease burden.
• Carotid atherosclerosis and cardiac embolic sources are common mechanisms.
• Giant cell arteritis accounts for a minority of cases but is disproportionately important because the fellow eye is threatened.
• The risk of additional vascular events is increased around the time of retinal artery occlusion.

Investigations

Initial Measures (Per Local Protocols)

Pharmacology

Prognosis / Complications

• Spontaneous meaningful visual recovery is limited in complete nonarteritic CRAO.
• A patent cilioretinal artery can preserve central vision and improve functional outcome.
• Arteritic CRAO often has severe visual prognosis and high fellow-eye risk without treatment.
• The major systemic prognostic issue is future stroke or cardiovascular disease.
• Low-vision rehabilitation and adaptive services can substantially improve function despite persistent acuity loss.

Patient Education / Counseling

• Explain that CRAO is treated as a stroke warning even if the affected eye does not regain vision.
• Call emergency services for any new neurologic symptoms or recurrent visual loss.
• Control blood pressure, diabetes, lipids, smoking, and atrial fibrillation according to the secondary-prevention plan.
• If giant cell arteritis is diagnosed, take corticosteroids exactly as prescribed and report symptoms in the other eye immediately.
• Discuss driving, fall prevention, occupational safety, and low-vision resources when vision remains impaired.
• Keep follow-up with ophthalmology and the stroke team because both ocular and systemic risks require management.

Notes

AAO guidance frames symptomatic retinal arterial occlusion as an emergency requiring immediate stroke-center assessment. The most important system-level error is treating it only as an isolated eye problem.

Vision-directed treatment remains an area of evolving evidence, but secondary vascular prevention is not optional. The episode may be the first sign of serious carotid or cardiac disease.

References

1. AAO Retinal and Ophthalmic Artery Occlusions Preferred Practice Pattern 2024 — Link
2. American Heart Association Acute Retinal Ischemia Resources — Link