CAVERNOUS SINUS SYNDROME DURING BALLOON TEST OCCLUSION OF THE CERVICAL INTERNAL CAROTID-ARTERY - REPORT OF 2 CASES

The authors report the occurrence of ipsilateral transient cavernous s inus syndrome during balloon test occlusion (BTO) of the cervical inte rnal carotid artery (ICA) and discuss the involved pathomechanisms. Th e authors reviewed their series of 129 BTOs of the ICA performed betwe en 1989 and 1996. Two patients developed facial paresthesias and trans ient palsies of the third through sixth cranial nerves during test occ lusion of the cervical ICA. The tests were performed prior to planned permanent carotid artery occlusion for the treatment of a neck sarcoma in one patient and a giant cavernous carotid artery aneurysm in the o ther. The patients' symptoms resolved with deflation of the balloon. W hen the balloon was subsequently inflated above the inferior cavernous sinus artery (ICSA), one of the patients complained of mild facial di scomfort. There was no contralateral weakness or mental status change during test occlusion in either patient. Angiography demonstrated good filling of the ipsilateral intracranial circulation via collateral ve ssels of the circle of Willis. In these two cases, the cranial nerves in the cavernous sinus were likely supplied by the ICA via the meningo hypophyseal trunk and the ICSA. In each case, there was excellent bloo d supply to the ipsilateral cerebral hemisphere; however, there was pr obably inadequate retrograde filling of the cranial nerve collateral v essels located where the meningohypophyseal trunk and ICSA originated. These cases emphasize the importance of a patent external carotid art ery-ICA connection for successful cervical carotid artery occlusion. N eurological examination during BTO was critical to interpret the clini cal manifestations caused by the hemodynamic changes.