Partial labyrinthectomy petrous apicectomy approach to neoplastic and vascular lesions of the petroclival area.

Objective: To study the value of an improvement of the presigmoid petrosal approach to the petroclival area by the addition of partial labyrinthectomy and petrous apicectomy and to document hearing and other results.

Methods: Thirty-six consecutive patients treated by this technique during a 2-year period were studied prospectively. The lesions treated included 33 petroclival neoplasms (25 meningiomas, 5 chordomas, 1 chondrosarcoma, 1 trigeminal schwannoma, and 1 epidermoid cyst) and 3 vertebrobasilar aneurysms. The patients underwent clinical, radiological, and neuro-otological examinations.

Results: There was no perioperative mortality. Cranial nerve deficits involving Cranial Nerves III, IV, V, and VI occurred in 17 patients (47%) postoperatively. Cerebrospinal fluid leak occurred in 12 patients (33%). Four of these patients were treated by lumbar drainage, two patients were treated by lumboperitoneal shunt, and six patients required reoperation and repacking of the middle ear. Hydrocephalus occurred in five patients (13.9%). There was one case of meningitis and another of systemic sepsis. All 36 patients underwent postoperative audiometric evaluation. When serviceable hearing was present preoperatively (Gardner-Robertson Grades I or II), it was determined to be preserved at postoperative follow-up in 81% of the patients (26 of 32 patients).

Conclusion: The partial labyrinthectomy petrous apicectomy approach provided improved access to neoplasms of the clivus and petrous apex and the posterior cavernous sinus area and to vertebrobasilar aneurysms in the midclival area. This improvement in access permits more controlled and thorough treatment of these lesions, with reduced brain retraction and acceptable morbidity with respect to auditory function.