Enlarged middle fossa vestibular schwannoma surgery: experience with 735 cases.

OBJECTIVE

To show the clinical outcome in patients with sporadic vestibular schwannoma (VS) operated on by the enlarged middle cranial fossa approach (EMFA).

STUDY

DESIGN

Retrospective case review.

SETTING

A tertiary referral center with four neurotologists experienced in EMFA surgery.

PATIENTS: There were 376 women and 359 men, with a mean age of 51.1 years (range, 12-77).

INTERVENTION: Enlarged middle cranial fossa approach surgery.

MAIN OUTCOME MEASURES: Magnetic resonance imaging and computed tomography scans were used for follow-up and re-evaluation of the operative sites. Facial nerve function and hearing were tested.

RESULTS

Overall complete VS removal was achieved in 97.1% of patients. There were two recurrences (0.3%) after microscopically complete tumor removal. Depending on the tumor size, postoperative normal and near-normal facial outcome ranged from 83% to 99% (average, 92%), and hearing at or near the preoperative level (+/-15 dB pure-tone average or +/-15% speech discrimination) was preserved in 60.2%, 48.2%, 23.9%, and 17.6%, respectively.

CONCLUSIONS

The EMFA is an excellent low-morbidity approach for VS removal with limited cerebellopontine angle extension (2 cm). Specific advantages of the EMFA are the superior internal auditory canal exposure, resulting in an extremely low tumor recurrence rate; best capability for hearing preservation; and minimal incidence of cerebrospinal fluid leaks. Postoperative facial function outcome compares with that of other surgical approaches. The best results are achieved in subjects with small tumors and good hearing, advocating early diagnosis and treatment.