[Fibromuscular dysplasia at the internal carotid origin: a case of carotid web]

A case of fibromuscular dysplasia at the internal carotid origin is reported. A 45-year-old, right-handed woman who was in good health, experienced 5-6 second episodes of numbness and tingling in her right hand and lip. She had no history of medical illness or trauma. The patient suffered the same sort of attack almost seven years after her first episode. General examination was unremarkable. There was no sign of residual neurologic deficit. Cerebral angiography demonstrated a discrete filling defect at the internal carotid origin. There was no evidence of atherosclerosis in the intracranial or extracranial vessels. The lesion occluded approximately 58% of the lumen. A carotid endarterectomy was performed and a "web shaped" tissue was removed from the posterior aspect of the right internal carotid artery. Microscopic examination of the surgical specimen demonstrated intimal fibrosis, consistent with the diagnosis of fibromuscular dysplasia. In addition to our patients, eight other cases of cephalic fibromuscular dysplasia have been reported in the form of an internal carotid web. This type of lesion is unique because the changes involve only the intima of the vessels without involvement of the medial structure as is seen in the usual form of fibromuscular dysplasia. Moreover, 5 out of 9 patients reported had the repeated episodes of the ischemic symptom, suggesting patients with this particular lesion have higher risk for stroke than those with the usual "string of beads" lesion. In these patients, surgical treatment should be considered, especially if medical therapy is unsuccessful.