What are the management options for Central Retinal Artery Occlusion (CRAO)?

Management of Central Retinal Artery Occlusion (CRAO)

CRAO should be treated as a medical emergency with rapid triage to the emergency department and consideration of intravenous tissue plasminogen activator (tPA) within 4.5 hours of symptom onset in eligible patients after a thorough benefit/risk discussion. 1, 2

Acute Management

Immediate Interventions

1. Emergency Department Triage

   • CRAO is an ocular emergency equivalent to acute ischemic stroke
   • Requires immediate medical attention 1, 2

2. Thrombolytic Therapy Options

   • Intravenous tPA:

     • May be considered in patients with disabling visual deficits
     • Must meet criteria for systemic tPA
     • Most effective when administered within 4.5 hours of symptom onset
     • Requires thorough benefit/risk discussion with patient 1, 2

   • Intra-arterial tPA:

     • May be considered in specialized centers with endovascular capabilities
     • Option for patients ineligible for IV tPA
     • Administered in increments of 15 mg with serial ophthalmological examinations
     • Maximum dose of 50 mg 1, 2
     • Caution: Currently an unproven therapy with potential risk of intracranial and systemic hemorrhage 3

Diagnostic Evaluation

• Structured neurological assessment using NIHSS
• CT brain without contrast to rule out hemorrhage
• Ophthalmological examination to confirm CRAO diagnosis 2
• Funduscopic examination to identify classic findings and rule out intraocular hemorrhage 1

Ineffective Conservative Treatments

• Evidence does not support the following interventions 1, 2:
  • Ocular massage
  • Anterior chamber paracentesis
  • Topical intraocular pressure-lowering agents
  • Sublingual isosorbide
  • Hemodilution (may be harmful)

Secondary Prevention

Vascular Risk Factor Management

• Aggressive control of:
  • Hypertension
  • Diabetes
  • Hyperlipidemia
  • Tobacco cessation
  • Weight management for obesity 1, 2

Antithrombotic Therapy

• Antiplatelet therapy: Reasonable when cause is cryptogenic or attributed to atherosclerosis
• Anticoagulation: May be appropriate if atrial fibrillation or other cardioembolic source is detected 1

Comprehensive Vascular Workup

• Carotid imaging
• Echocardiography
• Cardiac rhythm monitoring
• Consider surgical intervention for severe carotid artery stenosis 1, 2

Giant Cell Arteritis Screening

• Screen patients over 50 years (accounts for 5% of CRAO cases)
• If suspected, initiate urgent systemic corticosteroid therapy 2

Follow-up Care

Ophthalmological Monitoring

• Regular follow-up to monitor for neovascularization
• Closer monitoring for patients with greater retinal ischemia
• Panretinal photocoagulation if iris or retinal neovascularization develops 2

Collaborative Care

• Optimal management requires collaboration between:
  • Neurologist
  • Ophthalmologist
  • Primary care physician 1, 2

Important Clinical Considerations

Natural History and Prognosis

• Without treatment, only 17% of patients achieve functional visual acuity in the affected eye 1
• Spontaneous improvement may occur mainly during the first 7 days, with varying rates depending on CRAO type 4

CRAO Types and Differential Diagnosis

• Four distinct clinical entities:
  • Non-arteritic CRAO (most common)
  • Transient non-arteritic CRAO
  • Non-arteritic CRAO with cilioretinal artery sparing
  • Arteritic CRAO 4

Clinical Pitfalls to Avoid

1. Delayed recognition and treatment:

   • Time is critical - treatment efficacy decreases rapidly after symptom onset
   • Public education should emphasize painless, monocular visual loss as a stroke symptom 1, 2

2. Failure to conduct thorough vascular workup:

   • CRAO is associated with increased risk of future cerebrovascular and cardiovascular events
   • Management should focus on secondary prevention 5

3. Missing giant cell arteritis:

   • Can lead to bilateral vision loss if untreated
   • Requires immediate corticosteroid therapy when suspected 2

4. Relying on ineffective conservative treatments:

   • May delay definitive treatment
   • No evidence supports traditional approaches like ocular massage or paracentesis 1, 2