Intracranial carotid catastrophies encountered by the otolaryngologist.

Arteriographic studies are utilized to illustrate the presence and document the results of arterial ligation on three intracranial carotid aneurysms. All three aneurysms resulted from trauma, surgical and otherwise, and all presented as otolaryngologic dilemmas. All were successfully controlled by a combined Otolaryngological and Neurosurgical Team employing varying combinations of intra and extra cranial arterial ligations. None developed significant neurological impairments. The two major indications for common or internal carotid ligation are the resection of neoplasm and the control or prevention of hemorrhage. Sixty percent of patients undergoing elective carotid ligation survive these procedures without evidence of neurological sequelae. This uncompromised survival is based upon the presence or rapid development of collateral circulation to the cerebrovascular bed. Further arteriographic studies are employed to illustrate the development of intra and extra cranial collateralization to the internal carotid artery after surgical interruption of the ipsilateral common carotid. The major collateral circuits demonstrated via a case report are as follows: a. from the vertebral artery to the external carotid and hence to the internal carotid; b. from the posterior communicating artery to the internal carotid; and c. from the ophthalmic artery to the internal carotid.