前交通動脈瘤の流入動脈および動脈瘤柄部位とWillis動脈輪前半部の血流動態

Relationship between the Afferent Artery and the Site of Neck of Anterior Communicating Artery Aneurysm, and Hemodynamics in the Anterior Part of the Circle of Willis

Ⅰ．緒言

　前交通動脈瘤症例においては他の部の脳動脈瘤症例に比し，脳血管写上Willis動脈輪前半部の血流動態に異常を伴うものが多い．その大部分は一側の前大脳動脈A₁部形成不全により，しかも右A₁部形成不全が左A1部形成不全の約3倍を占めるということをわれわれはすでに報告した^5,6）．このWillis動脈輪前半部の血流動態異常，特に脳血管写上でのA₁部形成不全が前交通動脈瘤の流入動脈および動脈瘤柄部といかなる関係を有するかを検討したので報告する．

Of 346 patients with direct intracranial surgery for an aneurysm of anterior communicating artery that we have experienced from June 1961 to September 1975, 213 patients having sufficient data were selected to study a relationship between hypoplasia of the A1 of the anterior communicating artery, and sites of an afferent artery and a neck of an aneurysm.

1. Ninety seven of 182 patients who had had the bilateral angiography before surgery had hypoplasia of the right A1, 90 of which (92.8%) had an afferent artery of an aneurysm only in the left A1.