The Basilar Circulation in Otolaryngology

Syndromes of Basilar Artery Insufficiency  Sudden death following manipulation of the neck, for example in endoscopy, may be due to kinking of one of the vertebral arteries, with subsequent thrombosis. Thrombosis of the vertebral arteries or basilar artery may also occur spontaneously in patients with arteriosclerosis.¹It can be shown by injecting radio-opaque material into the vertebral arterial system of cadavers under continuous slight pressure that turning the head to the right causes constriction of the left vertebral artery at the level of the atlas and axis, and, vice versa, turning the head to the left causes constriction of the right vertebral artery at the same level.²The incidence of thrombosis of the basilar artery at necropsy in adults is 1 in 450 autopsies.³ About two-thirds of the patients were between 50 and 70 years of age.The histories obtained from 20 patients revealed fleeting and periodic