脳血管奇形と脳動脈瘤合併の蓋然性

CONGENITAL ANOMALIES OF CEREBRAL ARTERY AND INTRACRANIAL ANEURYSMS

I．はじめに

　脳動脈瘤はPolycystic Kidney^1,26），aortic coarcta—tion^2），Ehler-Danlos syndrome^3,4），Marfan syndrome^5）など先天奇形あるいは，胎生期遺残動脈例に合併しやすいとの報告^7,8,9）がある。著者らは，過去数年間に秋田県立脳血管研究所で施行された脳血管写ならびに剖検所見等につき，脳血管の異常例の出現頻度及び脳動脈瘤ないしは脳動脈奇形（以下AVMと略す）との合併例の検討を行なうと共に，各種脳血管障害に合併した脳動脈瘤との間に有意差があるか否かを検討した。その結果，いくつかの興味ある事実を得，さらに脳動脈瘤の成因につき，いささかの知見を得たので報告する。

It is well known that congenital anomalies suchas polycystic kidney, aortic coarctation, Marfansyndrome, Ehler-Danlos syndrome are apt to becomplicated by intracranial aneurysms. In thisreport we attempt to reveal the relation and in-cidence between cerebrovascular anomalies and intra-cranial aneurysms. The etiology of aneurysms hasbeen discussed, too. 12 cases of persistent trigeminlartery, 2 cases of persistent hypoglossal artery and11 cases of fenestration were obtained from 3841patients who were angiographically examined inour clinic for 5 years. The incidence is 0.31%,0.05% and 0.29%, respectively. Persistent tri-geminal arteries were complicated by 2 cases ofintracranial aneurysms and one case of arterivenousmalformations (AVM), persistent hypoglossal arteri-es were complicated by one case of aneurysm, andfenestrations were complicated by 2 cases of an-eurysms and one case of AVM. One case of con-genital agenesis of right internal carotid artery wasobtained which was complicated by aneurysm ofanterior communicating artery. Totally, 8 cases ofaneurysms and AVM were obtained from 26 casesof cerebrovascular anomalies (incidence 30. 8%). Onthe other hand, thalamic or caudate hemorrhagerevealed the highest incidence of complication ofintracranial aneurysms among intracerebral hema-tomas (10.7%). Compared with the incidence ofaneurysms between cerebro vascular anomalies(30.8%) and thalamic or caudate hemorrhage(10.7%), the difference is statistically significant(P<0.05). The cause of intracranial aneurysm hasnot yet been clarified. But it is well accepted thatthe defect of tunica media vasorum is most re-sponsible factor as to the occurrence of intracranialaneurysms.

We concluded that the genetic error of cerebralvessels including defect of media caused intracranialaneurysms, and this result was supported from theevidence that cerebrovascular anomalies showedstatistically high incidence of complication of intra-cranial aneurysms.