一側内頸動脈および対側総頸動脈閉塞後の脳側副循環について—脳側副循環の血管造影による研究 第1報

CEREBRAL COLLATERAL CIRCULATION FOLLOWING OCCLUSION OF COMMON CAROTID ARTERY ON ONE SIDE AND INTERNAL CAROTID ARTERY ON THE OTHER SIDE

I．はじめに

　頭蓋内動脈および頸部動脈閉塞症の脳循環とくにその側副循環に関しては，診断技術の進歩とくに高速連続血管撮影法，subtractionおよびカテーテル法による選択的血管造影法の普及に伴つて，最近興味ある報告が増加してきた。頭蓋内血管閉塞症においては，主として頭蓋内動脈分枝間の吻合および頭蓋内動脈と頭蓋外動脈との間に形成される側副循環路が脳循環に重要な役割を演じるが，頸部の主要動脈が閉塞すると，それ以外に頭蓋外の頸部動脈分枝間にも種々の側副循環路が新生される。

　これらの側副循環路は生理的な正常条件下にも存在し得るが，正常の血流路が何らかの原因によつて閉塞されると重要臓器の血流を十分に維持するために，閉塞のために生じた圧差に応じて側副吻合路が拡張増加して新しい血流路が形成される。

Cerebral collateral circulations following the com-mon carotid artery ligation on one side and the internal carotid artery ligation on the other side were described and demonstrated angiographically. Possible collaterals associated with cerebrovascular occlusion were also discussed. Total brachiocephalic arteriography was performed postoperatively on a patient, who had been treated by ligation of the common carotid on one side and the internal carotid on the other side, to evaluate the cerebral collateral circulation.

Angiography demonstrated on the side of internal carotid ligation, 1) collateral circulations between the vertebrobasilar and internal carotid systems via posterior communicating artery, 2) anastomoses bet-ween external and internal carotid arteries by wayof the back flow through the ophthalmic artery, 3) direct end-to-end leptomeningeal anastomoses bet-ween the parieto-occipital of the posterior cerebral artery, and the posterior parietal branch of the middle cerebral artery, 4) pericallosal communica-tions between the A. corporis callosi dorsalis of the posterior cerebral artery and the pericallosal of the anterior cerebral artery. Angiography showed on the side of the common carotid ligation, 1) collate-rals between the vertebro-basilar artery and internal carotid system via posterior communicating artery, 2) anastomoses between the vertebral artery, exter-nal and internal carotid artery with backflow from the external carotid at the bifurcation of the common carotid artery via vertebro-occipital anastomotic pathway. 3) collateral circulations between the sub-clavian artery and the internal carotid artery via the thyrocervical trunk, cervical collateral networks, occipital artery, external carotid artery and the bifurcation of the common carotid artery. 4) lepto-meningeal anastomoses between the terminal bran-ches of the posterior cerebral artery and the middle cerebral artery. 5) pericallosal communications be-tween the A. corporis callosi dorsalis and pericallosal artery over the splenium of the corpus callosum.