Middle Fossa
摘要
The middle fossa craniotomy approach to the lateral skull base is a versatile procedure that has become the workhorse for the surgical management of superior semicircular canal dehiscence (SCCD), cerebrospinal fluid (CSF) leaks and encephaloceles of the lateral skull base, primary facial nerve lesions and facial nerve trauma, and select vestibular schwannomas. The selection process for patients with vestibular schwannomas to pursue the middle fossa approach should include evaluation of preoperative hearing status, tumor size and location, and auditory brain response (ABR) and electronystagmography (ENG) results. Patients with better pure tone averages (PTA) and word recognition scores (WRS), smaller intracanalicular tumors with limited cerebellopontine angle (CPA) extension, ABRs with shorter interaural wave V latency, and ENG results suggesting tumors of the superior vestibular nerve have better outcomes and should be offered the middle fossa approach. With proper neurophysiologic monitoring, the middle fossa approach offers excellent hearing preservation and facial function outcomes with minimal associated complications.