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Updated: Jun 25, 2026
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A Murine Model of Ischemic Retinal Injury Induced by Transient Bilateral Common Carotid Artery Occlusion
Published on: November 12, 2020
From amaurosis fugax to asymptomatic bithalamic infarct
Journal of Neurology
|March 3, 2009
Summary
Bilateral paramedian thalamic infarction can be clinically silent, presenting only as transient monocular blindness. This case highlights cardiac embolism as a cause and the importance of detecting intermittent atrial fibrillation.
Area of Science:
- Neurology
- Cardiology
- Radiology
Background:
- Bilateral paramedian thalamic infarctions typically cause severe neurological deficits.
- Transient monocular blindness (amaurosis fugax) is often linked to carotid artery disease.
Observation:
- A healthy woman experienced amaurosis fugax after a Valsalva maneuver, with normal initial neurological and vascular assessments.
- MRI revealed silent bilateral paramedian thalamic ischemic lesions.
- Echocardiography identified a right-to-left shunt with atrial septal aneurysm.
- Ambulatory ECG monitoring detected intermittent, asymptomatic atrial fibrillation.
Findings:
- Silent bilateral paramedian thalamic infarction occurred, contrary to typical presentations.
- Cardiac embolism from an atrial communication was identified as the cause of amaurosis fugax.
- Intermittent atrial fibrillation, undetected by the patient, complicated management.
Implications:
- Thalamic infarcts can be clinically silent, necessitating advanced imaging.
- Cardiac sources, including undiagnosed atrial fibrillation, should be considered in amaurosis fugax.
- Thorough cardiac evaluation is crucial before procedures like patent foramen ovale closure.
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