Carotid Endarterectomy in Bilateral Stenosis of the Internal Carotid Artery

Twenty-four carotid endarterectomies (CEA) were performed in 22 cases of internal carotid (IC) stenosis. Nine had bilateral stenosis and 2 underwent CEA on both sides. Preoperative angiography showed other intracranial vascular lesions in 67% of the bilateral cases, and in 38% of the unilateral cases. Neurological signs in bilateral cases were major stroke in 3 patients (33%) and minor stroke in 6 patients (67%). On the other hand, minor stroke had occurred in only 8 patients (62%) and TIA was presented in 3 (33%) patients with unilateral lesion. Complete occlusion developed on one side in 2 of the bilateral stenosis 4 months after contralateral CEA. These facts suggested that arteriosclerotic change is severe and advanced in bilateral stenosis. And, when bilateral IC stenosis is found to be over 50% or with ulcer in the case of ischemic neurological deficits, bilateral CEA is recommended before complete occlusion. Good cross flow was demonstrated preoperatively in 46% of unilateral IC stenosis, but in bilateral cases only 11% had good cross flow, and 44% of them showed poor cross flow. EEG changes such as attenuation of background activity and slow waves following IC clamp were observed in 50% of bilateral stenosis and 20% of unilateral stenosis. During endarterectomy with operating microscope, an IC clamp is necessary to continue for about 60 min and an internal shunt is indicated to prevent hypoperfusion in every case, especially when associated with bilateral stenosis. CEA should be performed in the dominant side first, because this operation is for prophylaxis of further ischemic attack.