Fibromuscular dysplasia of the distal cervical internal carotid artery.

Fibromuscular dysplasia of the internal carotid artery is the most frequent extracranial localization of the disease. It can produce TIA or cerebral infarct through formation of fibrinous thrombi or complete occlusion of the artery. Seven cases are presented with disease localized in the distal segment of the carotid artery, usually considered inaccessible through standard exposure. A surgical approach is described to treat these lesions by performing a mandible osteotomy. This allows a resection of the internal carotid and its replacement with autologous saphenous vein graft as performed in six cases. The distal anastomosis was performed 1 or 2 cm. below the base of the skull. One case could not be corrected due to disease extending into the skull. All patients were operated on for TIA and one had a cerebral infarct. Six patients had an uneventful recovery and no further neurological symptoms. One patient had a postoperative hemiplegia. Pathologic specimens were described as fibromuscular dysplasia in all cases. Three of them had also a dissecting aneurysm, two of these also showed a ruptured intima. Intraluminal dilatation is regarded as a potentially risky procedure; resection and replacement through a mandible osteotomy is recommended for very distal internal carotid lesions.