From the Guidelines
The workup for amaurosis fugax should begin with a thorough history and physical examination, followed by urgent carotid imaging to identify potential sources of emboli, as this condition represents a transient ischemic attack affecting the retina and may precede a more devastating stroke, with the highest risk occurring within the first 48 hours after the initial event.
Key Components of the Workup
- Carotid duplex ultrasonography to assess for carotid stenosis, with CT angiography or MR angiography if significant stenosis is found 1
- Laboratory tests including complete blood count, erythrocyte sedimentation rate, C-reactive protein, lipid panel, and blood glucose to identify risk factors and inflammatory conditions
- Electrocardiogram and echocardiogram (transthoracic or transesophageal) to rule out cardiac sources of emboli
- Brain imaging with CT or MRI to evaluate for stroke or other intracranial pathology
- Ophthalmologic examination including fundoscopy to assess retinal circulation and rule out ocular causes
Initiation of Therapy
During the workup, patients should typically be started on antiplatelet therapy such as aspirin 81-325 mg daily unless contraindicated, as recommended by recent guidelines 1.
Urgency and Timing
The urgency of this workup is justified by the high risk of stroke within the first 48 hours after the initial event, and the fact that up to 24% of patients with amaurosis fugax have concurrent cerebrovascular accident on diffusion-weighted MRI, and up to 70% have significant systemic cardiovascular conditions, such as carotid stenosis 1.
Additional Considerations
The use of hyperbaric oxygen therapy has demonstrated efficacy in some cases, and panretinal photocoagulation with or without anti-vascular endothelial growth factor therapy may be recommended for patients who develop iris or retinal neovascularization 1.
Recent Guidelines
Recent guidelines recommend that acute retinal and ophthalmic artery occlusions be treated as a medical emergency and referred immediately to an emergency department or stroke center facility for neurological evaluation, due to the increased risk of central nervous system stroke 1.
From the Research
Workup for Amaurosis Fugax
The workup for amaurosis fugax involves a comprehensive evaluation to determine the underlying cause of the condition. Key components of the workup include:
- Medical history and physical examination to identify risk factors for atherosclerosis and cardiovascular disease 2, 3
- Ophthalmological examination to assess for signs of retinal ischemia, such as Hollenhorst plaques 4
- Carotid duplex scanning to evaluate for carotid artery stenosis, which is a common cause of amaurosis fugax 2, 3, 4
- Laboratory tests, such as complete blood count, blood chemistry, and lipid profile, to identify potential risk factors for atherosclerosis and cardiovascular disease 5
- Imaging studies, such as angiography, to evaluate the carotid and vertebral arteries for stenosis or other abnormalities 6
Diagnostic Considerations
When evaluating a patient with amaurosis fugax, it is essential to consider the following:
- The presence of risk factors for atherosclerosis and cardiovascular disease, such as hypertension, diabetes, and smoking 2, 3, 5
- The presence of signs of retinal ischemia, such as Hollenhorst plaques, which can indicate carotid artery stenosis 4
- The results of carotid duplex scanning and other imaging studies to evaluate for carotid artery stenosis and other abnormalities 2, 3, 4, 6
- The patient's medical history, including any history of ischemic stroke or transient ischemic attack (TIA) 5
Management and Treatment
The management and treatment of amaurosis fugax depend on the underlying cause of the condition. Key considerations include:
- Antiplatelet therapy to reduce the risk of ischemic stroke and other cardiovascular events 5
- Anticoagulant therapy in patients with a cardioembolic source of amaurosis fugax 5
- Carotid endarterectomy or other surgical interventions to treat carotid artery stenosis and prevent further episodes of amaurosis fugax 2, 3, 6
- Lifestyle modifications, such as smoking cessation and blood pressure control, to reduce the risk of atherosclerosis and cardiovascular disease 2, 3, 5