What is the appropriate work-up and treatment for a patient with acute onset vision change, considering potential underlying vascular events, previous eye conditions, and systemic diseases?

Acute Onset Vision Change Work-Up

Immediately refer any patient with acute painless vision loss to the nearest emergency department affiliated with a certified stroke center within 24 hours of symptom onset, as these patients are experiencing an "eye stroke" with high risk of concurrent or subsequent cerebral stroke. 1

Initial Triage and Urgent Actions

Same-Day Assessment Required

• Offer same-day appointments for all patients presenting with acute painless monocular vision loss, whether transient or permanent 1
• Document the exact timing of symptom onset, as patients presenting within 4.5 hours may be candidates for thrombolytic therapy 2
• Establish whether vision loss was transient (TMVL) or permanent (CRAO/BRAO), as both require identical urgent stroke workup 1

Critical History Elements

• For patients ≥50 years old: Specifically inquire about giant cell arteritis (GCA) symptoms including new headache, scalp tenderness, jaw claudication, temporal artery tenderness, malaise, fatigue, fever, diplopia, or history of polymyalgia rheumatica 1
• For all ages: Document history of transient ischemic symptoms, lateralizing weakness, paresthesias, cardiac disease, carotid disease, diabetes, hypertension, smoking, and hypercoagulable states 1

Immediate In-Office Evaluation

Essential Examination Components

• Visual acuity measurement in both eyes 1
• Pupillary examination for relative afferent pupillary defect 1
• Slit-lamp examination with careful iris inspection for neovascularization 1
• Intraocular pressure measurement 1
• Dilated fundoscopic examination looking for retinal whitening, cherry-red spot, emboli, or optic disc edema 1

Urgent Laboratory Tests (If GCA Suspected)

• Obtain immediate erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and complete blood count with platelets if patient is over 50 years old with any GCA symptoms 1
• Do not delay referral waiting for lab results - initiate high-dose systemic corticosteroids (1-2 mg/kg/day prednisone) immediately if GCA is strongly suspected to prevent vision loss in the fellow eye 1, 2

Emergency Department Referral Protocol

Immediate Referral Indications

• All patients with acute retinal artery occlusion (CRAO or BRAO) - even if vision has improved or reperfused 1, 2
• All patients with transient monocular vision loss (TMVL) within the past few days 1
• Any patient with suspected ophthalmic artery occlusion 1

Referral Communication

• Call ahead to the stroke center stating "a stroke patient is on the way" 1
• Provide written note clearly stating "Ocular TIA" or "Ocular Stroke" 1
• Explain to the patient that they are at risk for cerebral stroke (highest within first 7 days) and acute coronary syndrome 1, 2
• Emphasize that up to 25% of retinal artery occlusion patients have silent brain infarction on MRI 2

Stroke Center Diagnostic Workup

Neuroimaging (Within 24 Hours)

• Brain MRI with diffusion-weighted imaging (DWI) is preferred over CT to identify concurrent silent brain infarctions 1, 2
• If MRI unavailable, obtain head CT 1

Vascular Imaging

• Noninvasive cervicocephalic vessel imaging with MRA, CTA, or carotid ultrasound/transcranial Doppler 1
• Clinically significant carotid stenosis is discovered in up to 70% of patients with symptomatic retinal artery occlusions 2

Cardiac Evaluation

• Electrocardiography immediately 1
• Prolonged cardiac monitoring (inpatient telemetry or Holter) if etiology unclear after initial workup 1
• Echocardiography (at least transthoracic) is reasonable, especially when no cause identified; transesophageal echocardiography may be obtained to identify left atrial thrombus, patent foramen ovale, or valvular disease 1

Laboratory Studies

• Complete blood count with platelets, chemistry panel, hemoglobin A1C, prothrombin time/partial thromboplastin time, fasting lipid panel 1
• ESR and CRP in all patients >50 years old 1

Acute Treatment Considerations

Thrombolytic Therapy

• Intravenous tissue plasminogen activator (tPA) may be considered for patients presenting within 4.5 hours of symptom onset 2
• This requires immediate stroke center evaluation, as there is no proven benefit for attempting ocular-specific interventions in the office 1

Hyperbaric Oxygen

• Hyperbaric oxygen therapy (100% oxygen over 9 hours) has demonstrated efficacy in several small randomized trials 2

Giant Cell Arteritis Treatment

• Immediate systemic corticosteroid therapy for suspected arteritic retinal artery occlusion to prevent vision loss in the fellow eye 1, 2
• Monitor diabetic patients carefully as corticosteroids may destabilize glucose control 1

Age-Specific Workup Differences

Patients Over 50 Years Old

• Primary focus on embolic sources: carotid disease, cardiac sources, and GCA 1
• Mandatory ESR/CRP screening 1

Patients Under 50 Years Old

• Workup should focus on vasculitis and hypercoagulability 1
• Evaluate for antiphospholipid antibodies and other hematologic diatheses, autoimmune conditions 1

Follow-Up Management

Neovascularization Monitoring

• Patients with greater ischemia require closer and more frequent follow-up for iris or retinal neovascularization 1
• Undilated gonioscopy for iris neovascularization, especially when intraocular pressure is elevated 1
• Panretinal photocoagulation (PRP) with or without anti-VEGF therapy is recommended if neovascularization develops 1
• In acute cases, intravitreal anti-VEGF agents (off-label) may supplement or facilitate PRP treatment 1, 2

Secondary Prevention

• Antiplatelet therapy for the vast majority of patients 1
• Statin therapy 1
• Carotid endarterectomy for symptomatic carotid disease >70% stenosis; less certain benefit for 50-70% stenosis 1
• Optimize control of diabetes, hypertension, and lipid disorders 1
• Smoking cessation 1

Critical Pitfalls to Avoid

• Do not perform extensive in-office testing that delays emergency referral - the priority is immediate stroke center evaluation, not comprehensive ophthalmologic workup 1
• Do not assume that reperfusion or vision improvement eliminates the need for urgent evaluation - the stroke risk remains high even if vision has recovered 2
• Do not refer asymptomatic BRAO patients for expedited stroke workup - there is no conclusive evidence supporting this, though they should still receive timely evaluation 1
• Do not wait for laboratory results before referring - send the patient immediately while labs are pending 1
• Do not underestimate the urgency - stroke risk is 11.5% at 14 days and 18.8% at 90 days after retinal artery occlusion 1