Partial Mastoidectomy for the Safe Resection of Lateral Skull Base Tumors

Facial nerve dissection and mobilization is often necessary in the surgical resection of parapharyngeal, infratemporal, or extracranial jugular foramen tumors. Facial paralysis may occur as a result of a stretch injury at the stylomastoid foramen. Conversely, in an effort to protect the nerve, tumor spillage may occur, leading to the disastrous complication of disease recurrence.

Methods: Temporal bone laboratory specimens were used to demonstrate the pertinent landmarks used to quickly, yet safely, access the vertical (mastoid) segment of the facial nerve, as well as the stylomastoid foramen. The intraoperative technique involves soft-tissue dissection off the mastoid bone, utilizing a standard preauricular parotid or infratemporal incision. Release of the periosteal encasement at the stylomastoid foramen allows less stretch of the facial nerve during neural retraction and tumor removal.

Results: Individual case examples are presented to highlight the surgical technique used in the removal of a recurrent parotid tumor, a glomus vagale tumor, and a lower cranial nerve neuroma. The facial nerve results are detailed for a series of 32 patients managed at our institution between July 2000 and July 2006.

Conclusion: Transmastoid release of the facial nerve at the stylomastoid foramen allows for the safe dissection and retraction of the nerve for the removal of a variety of lateral skull base tumors. The surgical technique and overall results will be discussed along with specific case examples.