Hearing preservation in bilateral acoustic neuroma surgery.

Patients with neurofibromatosis type 2 (NF2) develop bilateral acoustic neuromas, but preservation of hearing while achieving tumor removal may present several unique problems. Our philosophy regarding hearing preservation attempts in these cases has evolved over several decades. The outcome of hearing preservation surgery using the middle cranial fossa approach for 13 procedures in 10 patients with NF2 is presented. There were 12 total tumor removals and one partial tumor removal. Two ears retained good postoperative hearing, three had serviceable hearing, four had measurable hearing, and four had no measurable hearing. Both cases with tumors 2 cm or larger retained no hearing. For the 12 total tumor removals, the rate of hearing preservation was 67 percent. Of four total removals with long-term follow-up, two retained good or serviceable hearing. The rate of hearing preservation is similar to that found in our series of unilateral acoustic neuroma surgeries. Based on these findings, hearing preservation surgery is recommended for patients with NF2 who have acoustic neuromas 1.5 cm or smaller.