Hearing restoration in NF2 patients and patients with vestibular schwannoma in the only hearing ear: report of two cases.

Objective: To explore audiologic outcome of auditory brain stem implantation (ABI) and cochlear implantation (CI) in NF2 patients and patients with vestibular schwannoma (VS) in the only hearing ear.

Patients And Methods: Study includes retrospective analysis of 2 cases. One is totally deaf patient due to NF2, and the other one is totally deaf due to VS development in only hearing ear. Tumor was removed by retrosigmoid approach in NF2 patient and ABI was performed simultaneously. For the VS in only hearing ear case, tumor was removed by translabyrinthine approach and CI was performed simultaneously.

Results: ABI patient showed quite well outcome during the 15 months of follow-up. She has 25 dB hearing threshold at speaking frequencies. She developed open set speech discrimination with 87.5% word discrimination score, and 70% sentence discrimination score. She uses device daily manner, she can use telephone. For CI patient, outcome is not perfect but satisfactory. She couldn't develop open set speech discrimination during the 18 months of follow-up. She has 67% the disyllabic words recognition score (close set). She is daily user of device. CI improves quite well lip reading.

Conclusion: ABI and CI are the two options to restore hearing in VS caused deafness. We advocate giving every effort to preserve cochlear nerve during the VS resection and place CI simultaneously. However if it is not possible to preserve cochlear nerve during surgery, ABI is also a good alternative for hearing restoration.