Surgical treatment of extracranial internal carotid artery aneurysm.

Aneurysms of the extracranial internal carotid artery are rare but can be responsible for severe complications such as rupture, thrombosis, or embolism. Between 1961 and 1985 we operated on 38 aneurysms of the extracranial internal carotid artery in 35 patients, 22 males and 13 females, whose ages ranged from 6 to 73 years. The underlying causes of aneurysm included atherosclerosis (12 cases), fibromuscular dysplasia (eight cases), a congenital defect (five cases), infection (one case), and trauma (six cases); in six cases aneurysm was secondary to spontaneous dissection. Signs of cerebral ischemia were present in 26 (74%) patients and a cervical mass was found in six. The aneurysm was proximal (i.e., below the angle of the mandible) in 16 patients and distal (i.e., above the angle of the mandible) in 22. After resection of the aneurysm, arterial continuity was restored in 37 patients by resection and grafting (12 cases), resection and anastomosis (11 cases), or arteriorrhaphy (14 cases). One death occurred 13 days after operation due to myocardial infarction. Two patients experienced a reversible neurologic event. Transient paresis of cranial nerves was observed in eight patients. During a follow-up period that ranged from 6 to 30 years, four patients were lost to follow-up and 25 patients remained asymptomatic. Three patients had asymptomatic thrombosis of the carotid artery detected at follow-up investigations. The potential risks of cerebral ischemia and rupture and the satisfactory long-term results achieved with surgery are strong arguments in favor of surgical treatment for aneurysms of the extracranial internal carotid artery.