Extended middle fossa approach to the petroclival junction and anterior cerebellopontine angle.

OBJECTIVES: This article seeks to demonstrate the use of the extended middle cranial fossa approach in the treatment of tumors arising in the anterior cerebellopontine angle and petroclival region.

STUDY DESIGN: We conducted a retrospective chart review.

SETTING: Tertiary referral center.

PATIENTS: : Ten-year retrospective chart review of over 800 skull base surgical cases demonstrated 16 cases in which the senior author used the extended middle cranial fossa as the sole approach to access the posterior cranial fossa, petroclival junction, or the anterior cerebellopontine angle. There were five males and 11 females, 13 meningiomas, 2 trigeminal schwannomas, and 1 brainstem glioma. Presenting symptoms were dependent on extent of brainstem compression and involvement of surrounding cranial nerves. The symptoms are broken down as follows: hydrocephalus, one; balance disturbance, three; diplopia, five; trigeminal neuralgia, two; hemifacial numbness, one; seizures, one; expressive aphasia, one; and hearing loss, two.

RESULTS: Of the 16 patients in this study, one patient needed postoperative care in a skilled nursing facility. Postoperative facial nerve weakness was not experienced in any patient. One patient developed a transient cerebrospinal fluid leak that resolved spontaneously. One patient developed a pseudomeningocele secondary to postoperative hydrocephalus. This was corrected with wound exploration and placement of a ventricular peritoneal shunt. Hearing was not maintained in one patient. Two patients developed new fourth nerve paresis and two patients developed new sixth nerve palsies. There were no postoperative infections and no deaths.

CONCLUSIONS: The extended middle cranial fossa approach provides excellent access and exposure to tumors in the anterior cerebellopontine angle and petroclival junction. The approach allows more direct access to the area anterior to the internal auditory canal. The key to the approach is adequate bone removal of the petrous apex to provide exposure down to the inferior petrosal sinus and anteriorly to Meckel's cave and the petroclival junction. Extradural elevation of the temporal lobe with suitable brain relaxation minimizes postoperative complications.