title: Puff of smoke.
mesh_terms: D000328:Adult; D002339:Carotid Arteries / Q000002:abnormalities; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging*; D002648:Child; D003097:Collateral Circulation; D005260:Female; D006429:Hemiplegia / Q000000981:diagnostic imaging; D006801:Humans; D011859:Radiography