Hearing preservation in neurofibromatosis type 2

Objective: The aim of the study was to provide a clinical review of the mid dle fossa approach for hearing preservation in patients with neurofibromato sis type 2 (NF2). Study Design: The study design was a prospective case review. Setting: The study was conducted at a private practice tertiary neurotologi c referral center. Patients: Eighteen patients diagnosed with NF2 underwent 23 middle fossa pr ocedures between 1992 and 1996 for removal of an acoustic neuroma. The nine males and nine females ranged in age from 11-73 years with a mean age of 2 8 years. Tumor size ranged from 0.5-2.5 cm with a mean of 1.1 cm. Main Outcome Measures: House-Brackmann facial nerve grade was measured. In addition, hearing level was classified both by the American Academy of Otol aryngology-Head and Neck Surgery criteria for reporting results of hearing preservation surgery and by comparison with preoperative level (15 dB/15%). Results: Measurable hearing was preserved in 65%, 48% within 15 dB of preop erative pure-tone average (PTA) and within 15% of preoperative speech discr imination. Bilateral hearing preservation occurred in five patients. Excell ent facial nerve function (House-Brackmann grades I-II) was obtained in all patients with normal preoperative facial nerve function. Conclusions: In this series of patients with NF2, outcomes in hearing and p reservation of preoperative facial nerve function are similar to results se en in patients suffering a sporadic unilateral acoustic neuroma. However, e arly intervention is crucial in obtaining such favorable outcomes.