Aneurysmal dilatation of torcula.
D002531:Cerebellum / Q000098:blood supply*; D002560:Cerebrovascular Circulation; D002675:Child, Preschool; D004108:Dilatation, Pathologic; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000000981:diagnostic imaging*; D008297:Male; D011859:Radiography