Fibromuscular dysplasia of the internal carotid arteries.

Seven patients with fibromuscular dysplasia of the internal carotid arteries have been operated upon at Walter Reed Army Medical Center. One lesion was treated by graduated dilatation with Bake's dilators combined with resection, end-to-end anastomosis, and vein patching of a tortuous segment. All other lesions were treated by graduated dilatation with an arterial dilator-shunt. All of these patients are asymptomatic presently. One patient has been operated upon recently because of symptoms related to the previously unoperated side as well as mild symptoms related to the previous operation. Two other patients with arteriographic evidence of fibromuscular dysplasia are being followed clinically. One is asymptomatic and one has minimal symptoms. Both are being treated with acetylsalicylic acid in hopes of preventing microembolization from these lesions. Important technical considerations in treating this condition are meticulous dissection of the internal carotid artery as near to the base of the skull as possible, confining the arteriotomy to the region of the carotid bulb, and straightening the carotid artery while passing the dilator under direct vision. A technique for routine shunting in these patients now is available.