What is the recommended workup for a patient presenting with Amaurosis fugax?

From the Guidelines

The recommended workup for a patient presenting with amaurosis fugax should begin with a thorough history and physical examination, followed by urgent carotid imaging (carotid ultrasound, CT angiography, or MR angiography) to assess for carotid stenosis, as this condition is often a warning sign of impending stroke, with the underlying pathophysiology typically involving emboli from carotid atherosclerotic disease or cardiac sources temporarily occluding the retinal artery 1.

Key Components of the Workup

• Complete blood count, lipid panel, blood glucose, ESR, and CRP should be ordered to evaluate for systemic causes.
• Brain imaging with MRI/MRI DWI is essential to rule out stroke, as up to 24% of these patients have concurrent cerebrovascular accident on diffusion weighted MRI 1.
• An ECG and echocardiogram (preferably transesophageal) should be performed to identify cardiac sources of emboli.
• Holter monitoring for 24-48 hours may detect paroxysmal atrial fibrillation.
• Ophthalmologic evaluation including fundoscopy is necessary to assess for retinal pathology.

Management Considerations

• While awaiting complete workup, patients should typically be started on antiplatelet therapy (aspirin 81-325 mg daily) unless contraindicated, as recommended by guidelines for patients with atrial fibrillation 1.
• If significant carotid stenosis (>70%) is identified, referral for carotid endarterectomy or stenting should be considered, as this can significantly reduce the risk of subsequent stroke 1.
• The use of hyperbaric oxygen therapy (100% oxygen over 9 hours) has demonstrated efficacy over observation alone in several small randomized trials for acute retinal ischemia 1.

Importance of Urgent Evaluation

• Growing evidence recommends that acute retinal artery occlusion (symptoms within 24 hours) be treated as a medical emergency and be referred immediately to an emergency department or stroke center facility for neurological evaluation because of the increased risk of central nervous system stroke 1.
• A patient with symptomatic retinal artery occlusion should be referred for an urgent evaluation within 1 week’s onset because the risk of stroke is highest within the first 7 days and remains elevated for 30 days 1.

From the Research

Recommended Workup for Amaurosis Fugax

The workup for a patient presenting with Amaurosis fugax typically involves a combination of the following:

• Non-invasive carotid artery studies, such as carotid duplex scan 2, bidirectional Doppler analysis, oculoplethysmography, carotid phonoangiography, and real-time B-mode ultrasonography 3
• Ophthalmic examination to rule out other causes of transient monocular blindness
• Laboratory studies to evaluate for risk factors such as hypertension, diabetes, coronary artery disease, tobacco, and hyperlipidemia 2, 4
• Cerebral computerized tomographic scan to rule out other neurologic disorders 3
• Consideration of angiography, although it may not be necessary in all cases, especially if non-invasive studies suggest significant ulcerated plaque 3

Evaluation Algorithm

The evaluation algorithm for Amaurosis fugax includes:

• Initial assessment with non-invasive carotid artery studies and ophthalmic examination
• Further evaluation with laboratory studies and cerebral computerized tomographic scan as needed
• Consideration of angiography and endovascular repair or carotid endarterectomy for patients with significant carotid stenosis or ulcerated plaque 2, 3, 5, 6

Treatment Options

Treatment options for Amaurosis fugax depend on the underlying cause and may include:

• Carotid endarterectomy for patients with significant carotid stenosis or ulcerated plaque 2, 4
• Endovascular repair, such as angioplasty and stenting, for patients with symptomatic external carotid artery stenosis or high surgical risk 6
• Medical management of risk factors, such as hypertension, diabetes, and hyperlipidemia 2, 5