[Intracranial arterial aneurysm. Differences in origin and prognosis in men and women].

A statistical model was defined from a series of 144 patients referred for a subarachnoid hemorrhage due to intracranial aneurysm rupture, occurred less than 3 days before admission. This model was then prospectively applied on a second series of 70 patients and allowed to find out four datas predicting the final functional result: age (p = 0.02), clinical status (p = 0.001), angiographic evidence of spasm (p = 0.01) and sex (p = 0.001). Concerning sex, functional result appears worse in women than in man. This more severe prognosis of aneurysmal rupture in woman is explained by the higher frequency of spasm (p less than 0.0005). This fact and the predominance of multiple aneurysms and localizations on the supraclinoid internal carotid artery (38.3% in females and 17.7% in males) suggest a different origin of intracranial aneurysms according to sex. Fibromuscular dysplasia might correspond to the datas here observed, and is currently explored.