Background: Auditory brainstem implants (ABI) continue to serve an important role in the treatment
of deafness for patients with neurofibromatosis type 2 (NF2). ABI is also demonstrating
promising results for patients without NF2 yet still suffering from pathology that
prevents reliable signal transmission from the cochlear nerve. As a technology still
in its infancy, outcomes have shown wide variability between centers as candidacy
criteria, device design, operative technique, and postoperative programming and rehabilitation
strategies evolve. We sought to characterize the evolution of ABI performance at our
center, and determine key factors influencing satisfactory postoperative outcomes
over time.
Methods: A single-center retrospective chart review was completed for 28 patients from 2016
to 2022 who underwent ABI at a tertiary referral center. Demographic data, indication,
contralateral cochlear implant status, surgical approach and use of intraoperative
electrically evoked auditory brainstem response (EABR) were gathered. For patients
implanted with NF2, tumor size and treatment history were also analyzed. Our primary
outcome was open-set word recognition or age appropriate speech perception and production
assessments. Secondary outcomes included hours per day of use and postoperative complications
Results: A range of auditory performance was found for ABI recipients, with improved audiological
outcomes found in patients implanted more recently in the ABI program, and in patients
who received an implant for an indication other than tumor. Complication rates were
found to be low.
Conclusions: For patients not amenable to cochlear implantation, ABI continues to provide the
possibility of improved communication and access to environmental sounds. Patients
who undergo ABI for indications other than NF2 also demonstrate utility in carefully
selected cases and should not be precluded from ABI candidacy. Further research into
the use of pre-operative imaging to characterize auditory pathway integrity for ABI
prognostication and ABI placement decisions is warranted.
