Vertebrobasilar insufficiency.
D001488:Basilar Artery / Q000000981:diagnostic imaging; D003097:Collateral Circulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D014711:Vertebral Artery / Q000000981:diagnostic imaging; D014715:Vertebrobasilar Insufficiency / Q000175:diagnosis* / Q000000981:diagnostic imaging