Neural response telemetry and auditory/nonauditory sensations in 15 recipients of auditory brainstem implants

Auditory brainstem implants (ABIs) provide a means of restoring some hearing sensations to individuals with neurofibromatosis type 2 (NF2) who are deaf after vestibular schwannoma removal. In this study, neural response telemetry (NRT) was used to record electrically evoked neuronal activity near the ABI electrode array in 15 such subjects. Our interest was to investigate whether NRT recordings from the brainstem might be useful in implanting or programming ABIs. We therefore sought relationships between postoperative NRT recordings and the sensations reported by the subjects in response to the test stimuli. However, no clear relationships among these variables were found, and it was not possible to differentiate recordings associated with auditory versus nonauditory sensations. The findings suggest that the categorization of NRT recordings used in this study is inappropriate for assisting with placement of an ABI electrode array intra-operatively or for programming the sound processor postoperatively.