Association between Eye Infarction and Carotid Stenosis
Pathophysiological Association
- The most common cause of eye infarction (retinal ischemia) is atherosclerosis of the ipsilateral internal carotid artery, according to the American College of Cardiology 1
- Retinal ischemia occurs due to thromboemboli from atherosclerotic plaques of the carotid arteries, atheroemboli from cholesterol crystals or other atheromatous material, acute thrombotic occlusions of an extracranial artery due to plaque rupture, or reduced cerebral perfusion due to critical stenosis or occlusions 2, 3, 4, 5
Clinical Manifestations
- Monocular vision disturbances (transient monocular blindness/amaurosis fugax) are typical symptoms of carotid stenosis, as reported by the American Academy of Ophthalmology 6
- Symptoms and signs of ischemia or infarction in the territory of the right internal carotid artery or middle cerebral artery include monocular blindness of the right eye, according to the American Heart Association 2, 3
Diagnostic Findings
- Up to 70% of patients with symptomatic ocular vascular events have a clinically significant carotid stenosis, as stated by the American College of Cardiology 1
- In patients with acute retinal ischemia, multiple small cerebral infarcts are found in up to 31% of cases, which are associated with ipsilateral atheromatous carotid stenosis, according to the American Academy of Ophthalmology 7
Diagnostic Procedure
- In cases of suspected eye infarction, immediate referral to an emergency department or stroke center for neurological examination within 24 hours of symptom onset is recommended by the American College of Cardiology 1
- Diffusion-weighted MRI of the brain should be performed, as silent brain infarcts are present in up to 24% of patients with acute ocular vascular events, as reported by the American College of Cardiology 1
Risk Assessment and Prognosis
- The risk of stroke in patients with amaurosis fugax is highest in the first 7 days and remains elevated for 30 days after the initial event, according to the American College of Cardiology 1
- The 3-year stroke risk is:
Therapeutic Consequences
- Antiplatelet therapy (75-325 mg aspirin daily) is recommended for patients with documented amaurosis fugax, according to the American College of Cardiology 1
Common Pitfalls
- Delayed referral to emergency services or a stroke center (should occur within 24 hours), as reported by the American College of Cardiology 1
- Oversights of silent brain infarcts in imaging, which can be present despite transient symptoms, according to the American College of Cardiology 1
- Underestimation of the systemic significance of an eye infarction, which serves as a warning sign for increased stroke and cardiovascular risk, as stated by the American Academy of Ophthalmology 7