Combined Supra-Infratentorial Microsurgical Approach for Petroclival and Tentorial-Incisural Extra-Axial Lesions

Background: Microsurgical removal of extra-axial lesions in the petroclival region is one of the most challenging procedures in neurosurgery.

Objective: The objective of this report is to describe the fundamental anatomic concepts, surgical principles, and strategies as well as results in a series of 24 patients who underwent the supra-infratentorial petrosal approach for removal of petroclival and tentorial-incisural lesions

Material and Methods: Thirteen petroclival meningiomas, 3 tentorial meningiomas, 6 vestibular schwannomas, and 2 trigeminal schwannomas underwent microsurgical removal using the supra-infratentorial approach in conjunction with petrosectomy (22 translabyrinthine, 2 retrolabyrinthine). The surgical principles and strategies followed were: (1) translabyrinthine or retrolabyrinthine petrosectomy that opens the surgical corridor anteriorly, (2) mobilization of the sigmoid sinus that opens the surgical corridor posteriorly, (3) excision of the tentorium that provides additional space in the depth, (4) avoidance of vascular (arterial and venous) and neural injury, (5) adequate initial tumor decompression that opens the tumor-arachnoid interface, and (6) attention to detail (hemostasis/closure).

Results: Simpson grades 1 and 2 removal was accomplished in 16 patients. There were no operative mortalities. Complications included ipsilateral hearing loss (22), House-Brackmann II facial paresis (4), trigeminal sensory loss and CSF rhinorrhea (2 each), and worsened hemiparesis (1). There were three recurrences. The median follow-up period was 85 months (range, 6–164 months).

Conclusion: Adequate exposure is necessary for a meaningful and safe resection of petroclival tumors. We feel that sacrificing ipsilateral hearing was justified in order to access and safely remove these life-threatening tumors.