Small carotid thrombus and minimal stenosis causing repeated embolic strokes
1Department of Neurosurgery, University of New Mexico, Albuquerque, NM, USA. htran@salud.unm.edu
Summary
A rare cause of stroke, minimal carotid artery stenosis, can lead to cerebral infarctions. Early diagnosis via computed tomographic angiography is crucial for effective treatment and preventing further neurological damage.
Area of Science:
- Neurology
- Vascular Surgery
- Radiology
Background:
- Undiagnosed stroke sources remain a challenge in neuroradiology, affecting 28% of cases.
- Embolic sources from minimal carotid artery stenosis are infrequently reported.
- Cerebrovascular events often lack identifiable risk factors in certain patient demographics.
Observation:
- A healthy 48-year-old woman experienced multiple cerebral infarctions in the right anterior and middle cerebral artery territories.
- Initial cardiac and cerebral vessel imaging failed to detect a small abnormality on the internal carotid artery's posterior wall.
- Computed tomographic angiography ultimately diagnosed the lesion, which was overlooked by North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria.
Findings:
- The patient's condition worsened despite maximal antiplatelet and anticoagulation therapy.
- Carotid endarterectomy was performed, resulting in no new embolic events.
- Histopathology revealed endothelial hyperplasia with organizing thrombus, likely hemodynamically induced on an atherosclerotic plaque.
Implications:
- This case highlights the diagnostic limitations of current neuroradiological assessments for certain embolic stroke sources.
- It underscores the importance of advanced imaging like computed tomographic angiography in identifying subtle carotid artery abnormalities.
- The findings suggest that even minimal carotid stenosis can be a significant embolic source, necessitating tailored surgical or medical management.
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