Combined surgical approaches through the temporal bone: surgical anatomy, pitfalls and complications. lessons learned in a series of 36 patients

Objective: "Combined" surgical approaches through the temporal bone provide access to more than one intra/extra cranial fossa or compartment. Though their general usefulness has not been questioned, their safety and specific applications have varied widely. Our aim is to discuss the surgical anatomy, pitfalls and complications of those approaches. Methods and Results: A retrospective analysis of a total of 36 patients who had undergone combined surgical approaches through the temporal bone between November 1995 and October 2000 under the neurosurgical care of the senior author (JJM) were reviewed. Ages range from 18 to 71 years with a mean age of 50 years. Male to female ratio was 18 to 18. Pathologies included 14 meningiomas, 6 chondrosarcomas, 4 durai arteriovenous malformations, 3 aneurysms, 2 acoustic neuromas, 2 glomus jugulare tumors, 1 trigeminal schwannoma, 1 craniopharyngioma, 1 epidermoid tumor, 1 hemangiopericytoma, and 1 mucocele of the petrous apex. Surgical approaches were divided into the following groups: a) anterior petrosal or Kawase approach (n=4); b) posterior petrosal combined with subtemporal approach (n=21); c) combined posterior and anterior petrosal approach (n=3); d) "other combinations" (n=8). Posterior petrosal combined with subtemporal approach included retrolabyrinthine, partial translabyrinthine, translabyrinthine, transcochlear and transotic approaches. The "other combinations" included the following approaches: combined retrolabyrinthine or translabyrinthine with jugular foramen, combined-combined, and total petrosectomy. Clinical outcome and complications are analyzed and presented in detail as they relate to specific approaches. Anatomical dissections in the laboratory were also performed to rationalize the use of specific approaches for specific pathologies at specific location. Conclusion: Combined surgical approaches through the temporal bone enable surgical treatment of various pathologies in the petroclival region in a safe and effective manner. A better understanding of the interaction of surgical anatomy with nature and extent of the lesion, along with refinements of each approach, are of great importance in improving outcome and complication avoidance.