True and false external carotid steals.
D000368:Aged; D001488:Basilar Artery / Q000000981:diagnostic imaging; D001783:Blood Flow Velocity; D002341:Carotid Artery Thrombosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002342:Carotid Artery, External / Q000000981:diagnostic imaging; D002404:Catheterization; D002533:Cerebral Angiography; D003097:Collateral Circulation; D006801:Humans; D008297:Male; D008875:Middle Aged; D055585:Physical Phenomena; D010825:Physics; D014711:Vertebral Artery / Q000000981:diagnostic imaging