[Limits of preventive extra-intracranial anastomoses. A propos of a meningioma of the clinoid process with stenosis of the internal carotid artery].

In the case reported here a voluminous meningioma attached to the anterior clinoid process had invaded the cavernous sinus, involving and constricting the internal carotid artery and its terminal branches. To prevent occlusion of the carotid-sylvian system during surgery, an extra-intracranial anastomosis was carried out and its permeability was controlled and confirmed. However, excision of the meningioma, which entailed resection of the carotid segment, resulted in hemiplegia. The authors emphasize the importance of haemodynamic and anatomical factors in such cases.