What is the initial workup and management for a patient with central retinal artery occlusion?

Central Retinal Artery Occlusion Workup and Management

Patients with suspected CRAO require immediate emergency department transfer without delay, as this is an ocular stroke with a narrow 4.5-hour therapeutic window for potential thrombolysis. 1

Immediate Triage and Time-Critical Actions

Communicate to emergency providers that the patient has experienced an "eye stroke" to ensure appropriate triage priority. 1 The therapeutic window for meaningful intervention is extremely narrow—ideally within 4.5 hours of symptom onset for IV tPA consideration. 1

Emergency Department Evaluation

The initial diagnostic workup must include:

• Funduscopic examination to confirm diagnosis showing retinal whitening with cherry-red spot 1
• Relative afferent pupillary defect assessment, which is a classic finding 2
• ESR and CRP urgently in all patients over 50 years of age to rule out giant cell arteritis 1
• Brain MRI with diffusion-weighted imaging, as 19-25% of patients have concurrent silent brain infarctions 1
• Vascular imaging to assess carotid artery status, since up to 70% have clinically significant carotid stenosis 1

Acute Treatment Considerations

Intravenous Thrombolysis

For patients presenting within 4.5 hours of symptom onset, intravenous tPA may be considered at 0.9 mg/kg (10% given over 1 minute, remainder over 59 minutes) after thorough benefit/risk discussion. 1 This decision rests on equipoise in the current literature, as fully powered efficacy trials are still pending. 2

The evidence shows:

• IV thrombolysis within 4.5 hours increases functional visual recovery to approximately 39% (achieving 20/100 or better vision) compared to 17.7% with natural history alone 3
• No recorded cases of symptomatic intracranial hemorrhage when tPA is administered within 4.5 hours without concomitant anticoagulation 2
• The EAGLE trial failed to show benefit, but patients were treated at a mean of 13 hours—well outside the therapeutic window 2, 3

Giant Cell Arteritis Exclusion

In patients over 50 years of age, if GCA is diagnosed or highly suspected, initiate immediate high-dose systemic corticosteroids (typically IV methylprednisolone 1g daily for 3 days). 1 This is critical to prevent vision loss in the contralateral eye, as arteritic CRAO accounts for 5% of cases. 2

Intra-arterial Therapy

Intra-arterial tPA at early time points remains untested but may be considered at centers with endovascular capabilities. 2 However, the EAGLE trial showed no benefit and two patients had intracerebral hemorrhage, though treatment occurred at a mean of 13 hours. 2 The technical challenges are substantial given the ophthalmic artery is only 1.3 mm in diameter and the central retinal artery is 160 µm at its terminus. 2

Secondary Prevention Workup

All patients with CRAO require systematic evaluation for thromboembolic sources and vascular risk factors. 1

Vascular and Cardiac Evaluation

• Carotid artery imaging for occlusive disease 1
• Cardiac valve disease assessment 1
• Thromboembolic disease evaluation 1
• Assessment for hypertension, hyperlipidemia, diabetes, tobacco exposure, and obesity 2

Age-Specific Considerations

• In younger patients (<50 years): workup for vasculitis or hypercoagulability 4
• In older patients (>50 years): embolic workup is the priority 4

Stroke Risk Assessment

The risk of stroke is highest within the first 7 days after CRAO and remains elevated for 30 days. 1 Up to 24% of patients have concurrent cerebrovascular accident on diffusion-weighted MRI. 1 This underscores why CRAO should be managed as part of the acute ischemic stroke spectrum. 2

Prognosis and Quality of Life Impact

Without treatment, over 80% of patients present with visual acuity of "count fingers" or worse, and nearly 80% maintain this severe visual disability at final follow-up. 3 The natural history is poor, with only 17.7% achieving functional visual acuity (20/100 or better) in the affected eye. 2, 3

The quality of life impact is substantial:

• Increased fall risk (odds ratio 2.86) 1, 3
• Increased functional dependence (odds ratio 7.50) 1, 3
• May be disabling enough to warrant placement in long-term care facility 1
• Limitations in physical and social functioning with emotional distress 1

Critical Pitfalls to Avoid

• Do not delay transfer for outpatient ophthalmology evaluation—immediate ED transfer is mandatory 4, 1
• Do not assume conservative treatments (ocular massage, anterior chamber paracentesis, IOP-lowering agents) are effective—these lack evidence for benefit 2
• Do not miss giant cell arteritis in patients over 50—this is the one preventable cause of bilateral blindness 1
• Do not treat beyond 4.5 hours expecting benefit—experimental evidence shows retinal ganglion cells suffer irreversible damage after 240 minutes 3