From the Guidelines
Amaurosis fugax is a transient monocular blindness caused by temporary reduction of blood flow to an eye, often described as a shade drawn upward or downward over the field of view, and is a warning sign of potential stroke. This condition is typically characterized by a sudden loss of vision in one eye, which may last for a few minutes before vision returns to normal 1. The most common cause of amaurosis fugax is atherosclerosis of the ipsilateral internal carotid artery, but other causes include carotid artery stenosis or occlusion, dissection, arteritis, radiation-induced arteriopathy, arterial embolism, cardiogenic embolism, atheroembolism, hypotension, intracranial hypertension, glaucoma, migraine, and vasospastic or occlusive disease of the ophthalmic artery 1.
Key Points
- Amaurosis fugax is a warning sign of potential stroke and requires immediate medical attention
- The most common cause is carotid artery disease, where plaque builds up in the arteries that supply blood to the brain and eyes
- Other causes include heart problems that can produce emboli, blood disorders, vasculitis, or migraine
- Treatment typically focuses on addressing the underlying cause and may include antiplatelet medications, blood thinners, cholesterol-lowering drugs, blood pressure control, and in some cases, surgical procedures like carotid endarterectomy to remove plaque from the carotid artery 1
- Lifestyle modifications including smoking cessation, regular exercise, and a heart-healthy diet are also important components of management
Management
The management of amaurosis fugax involves addressing the underlying cause of the condition. Treatment should focus on reducing the risk of stroke and preventing further episodes of transient monocular blindness. This may include medications such as aspirin (81-325mg daily) or clopidogrel (75mg daily) to prevent blood clots, as well as cholesterol-lowering drugs and blood pressure control 1. In some cases, surgical procedures like carotid endarterectomy may be necessary to remove plaque from the carotid artery. Lifestyle modifications, including smoking cessation, regular exercise, and a heart-healthy diet, are also important components of management.
From the Research
Definition of Amaurosis Fugax
- Amaurosis fugax (AF) is a term used to denote momentary visual loss from transient retinal ischemia 2
- It is a type of transient ischemic attack (TIA) that occurs in the retina, characterized by a temporary loss of vision in one eye 2
Causes and Risk Factors
- AF is often associated with atherosclerotic lesions in the carotid artery, which can be potentially treatable by carotid endarterectomy 3
- Risk factors for significant carotid stenosis in patients with AF include male sex, current smoking, diabetes, and previous vasculitis 4
- Other potential causes of AF include migraine, heart disease, and platelet disorders 3
Diagnosis and Management
- Patients with suspected AF should be expeditiously evaluated, including a detailed history and examination, followed by specific diagnostic studies such as imaging of the brain and extracranial and intracranial blood vessels 2
- Cardiac investigations and serum studies to evaluate for etiological risk factors are also recommended 2
- Management of AF should focus on stroke prevention strategies, including antiplatelet therapy, lifestyle modifications, and management of traditional risk factors such as hypertension, dyslipidemia, and diabetes 2
- Carotid endarterectomy may be indicated in patients with significant carotid stenosis, but the decision to operate should be based on individual patient characteristics and risk factors 5, 6