Introduction: Carotid atherosclerosis is a known risk factor for acute ischemic stroke. While severe luminal narrowing is a well-established risk factor for future ischemic events, up to ten-percent of patients with acute ischemic stroke or TIA are thought to have ischemic events secondary to vulnerable carotid plaques in the setting of mild to moderate carotid artery stenosis.
Results: The patient is a 78 year-old male with a PMHx significant for a MI and atrial fibrillation on Plavix, aspirin and Warfarin. He developed a short “spell” while eating where he “froze up and could not talk.” An MRI showed acute infarcts in the left MCA and ACA territories. An EEG and TEE were negative. He later experienced numerous recurrent similar episodes, again while eating, with imaging showing a new infarct in the left corpus callosum. As a result of these recurrent spells which occurred only with eating, he had significantly decreased his oral intake and eventually experienced a weight loss of 14 lbs.
A neck MRA demonstrated a 20% stenosis of the proximal left ICA with a markedly T1 hyperintense plaque and peripheral enhancement. This was consistent with a vulnerable plaque with both intraplaque hemorrhage and lipid rich necrotic core. The involved carotid segment was retropharyngeal which could have explained mechanical “squeezing” of the vulnerable plaque while eating with distal emboli. He eventually underwent a carotid endarterectomy without complications with resolution of his symptoms.
Conclusions: We present a unique case of recurrent ischemic stroke that occurred only with eating secondary to a vulnerable, non-stenotic, plaque in a patient with a retropharyngeal carotid artery. We hypothesize that the mechanical “squeeze” of the vulnerable plaque involving the retropharyngeal proximal ICA was related to the multiple recurrent TIAs which, characteristically occurred only while eating.
Patient Care: A number of patients fall out of the NASCET guidelines for treatment of symptomatic carotid artery disease. Hopefully, this report will help select the best treatment course for certain patients with low-grade stenosis by taking into account the unusual imaging findings and clinical presentation.
Learning Objectives: By the conclusion of this session, participants should be able to: 1)Recognize imaging characteristics of a "hot" or vulnerable plaque.
2) Identify an anatomic variant of the ICA
and 3)Identify potential patients with low-grade stenosis who may benefit from endovascular or surgical procedures
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