対側に高度閉塞性病変を伴った頚動脈高度狭窄例の脳循環動態の特徴と治療

Abstract

Treatment of cervical carotid stenosis with the contralateral internal carotid artery (ICA) occlusion or severe stenosis has not been established because of its specific cerebral circulation. We sought to clarify the clinical features and best surgical treatment of cervical severe carotid stenosis with contralateral ICA occlusion or severe stenosis.We studied 8 patients with bilateral severe ICA stenosis (≥70%) and 5 patients with ICA severe stenosis and contralateral ICA occlusion. To evaluate cerebral circulation, regional cerebral blood flow (rCBF) of the middle cerebral arterial territory and stump pressure of the ICA were measured. rCBF was measured before and after CEA. Rates of association of systemic diseases were analyzed. There was no perioperative complication or new stroke in the follow-up time (2-138 months) in this series. In 3 of the 8 patients, rCBFs were bilaterally decreased below 40 ml/100 g/min. rCBF of severe ICA stenosis with contralateral ICA occlusion or severe stenosis was lower than that of unilateral ICA stenosis. In 6 of 9 patients who underwent CEA, rCBF increased over 15% after operation. Stump pressures of the ICA in the patients with severe ICA stenosis associated with contralateral ICA occlusion or severe stenosis were significantly (p<0.05) lower than those of unilateral ICA stenosis. SEP became flat during ICA cross-clamping in 4 patients but recovered after reflow of the ICA. Bilateral ICA occlusive disease had been highly associated with ischemic heart disease compared with unilateral stenosis. In the follow-up period, 4 patients had angina pectoris and 2 patients had coronary artery bypass grafting surgery.The patients with bilateral severe occlusive disease had low rCBF and low collateral flow. Because of low collateral flow via Willis ring, an internal shunt was necessary to avoid cerebral ischemic complication during ICA cross-clamping. SEP was useful for detecting cerebral ischemia during ICA cross-clamping. Vascular reconstruction increased rCBF, especially in the patients with low rCBF. The treatment of patients with ischemic heart disease is very important but controversial.