[Evaluation of a group of cases presenting an abnormal vascular network at the base of the brain].
D000293:Adolescent; D002533:Cerebral Angiography; D002648:Child; D002675:Child, Preschool; D002941:Circle of Willis / Q000002:abnormalities*; D003097:Collateral Circulation; D005260:Female; D006801:Humans; D008297:Male