Facing a Feared Situation: Endoscopic Endonasal Approach for Petroclival Lesions With Internal Carotid Artery Encasement: 2-Dimensional Operative Video.

A 33-yr-old woman presented with diplopia due to partial III and VI cranial nerve palsies, and an magnetic resonance imaging (MRI) showed a left petroclival lesion with cavernous sinus invasion. The ipsilateral internal carotid artery (ICA) was displaced and encased by the tumor. Chondroid tumors such as this are known to be high risk for ICA injury1; however, given the patient's young age a radical resection was desirable,2 depending on the risk of such a strategy. Therefore, a preoperative balloon test occlusion (BTO) was performed to estimate the risk of stroke in case of ICA sacrifice.3 Clinical and single-photon emission computed tomography testing predicted low risk of stroke, allowing for aggressive resection. A preoperative ICA occlusion was not performed as intraoperative control was believed to be adequate and preservation is always preferable when possible due to rare inaccuracies in BTO and long term risks of occlusion. An endoscopic endonasal and right contralateral transmaxillary approach with intraoperative neurophysiology were performed to remove this lesion.4,5 During surgery, the ICA proved dehiscent, and was therefore clip sacrificed.6 An immediate postoperative digital subtraction angiography showed minimally delayed, but adequate, blood flow to the left cerebral hemisphere. Postoperative MRI showed complete removal and no significant infarct. The patient was discharged in stable neurological condition, with only a slightly worsened CN III palsy. Experience with management of ICA injury is of uttermost importance in endoscopic endonasal surgery,1,2 and requires adequate training and an experienced 2-surgeon team.7 The patient provided consent to the submission and publication of the related surgical video.