When Cryptogenic Is Not Cryptogenic: Carotid Web as a Cause of Recurrent Embolic Stroke.

A carotid web is an under-recognized vascular abnormality increasingly identified as a cause of embolic ischemic stroke in younger patients without conventional vascular risk factors. Delayed diagnosis may lead to recurrent cerebrovascular events despite otherwise unrevealing investigations.  We report the case of a 35-year-old woman who experienced three ischemic strokes over a three-year period. Initial investigations, including carotid Doppler ultrasonography, cardiac evaluation, CT angiography, and a young stroke laboratory screen, did not identify a clear etiology. Ongoing clinical suspicion in the setting of recurrent embolic events prompted further vascular reassessment. A subsequent MRI of the neck with magnetic resonance angiography demonstrated an abnormality of the proximal left internal carotid artery suggestive of a carotid web, and hence, repeated CT angiography confirmed the diagnosis. The patient underwent carotid endarterectomy, with operative confirmation of the diagnosis.  This case highlights carotid webs as an important and potentially treatable cause of recurrent embolic strokes. Increased awareness and careful review of vascular imaging may facilitate earlier diagnosis and prevention of further cerebrovascular events.