Using Cortical Auditory Evoked Potentials in Active Middle Ear and Bone Conduction Implant Users: An Objective Method to Optimize the Fitting

Objective The study aimed to investigate whether cortical auditory evoked potential (CAEP) measures could be used to optimize active middle ear implant (aMEI) and bone conduction implant (BCI) fitting, with the goal of improving hearing outcomes in adults. Design CAEPs were measured in response to LING sounds /OO/, /AH/, and /SH/ presented in sound field. If CAEP responses were recorded for all sounds, no map adjustments were performed. If a CAEP response was absent for one or more sounds, map parameters were optimized until a CAEP response could be induced. Functional outcomes were measured as pre- vs postoptimization adaptive speech-in-noise results. Subjective feedback was also collected. Results Of the 15 participants, one was excluded from the study, three did not need optimization, nine were successfully optimized using CAEP measurements, and two could not be optimized. Comparison of CAEP morphology showed significant differences pre- vs postoptimization for middle- and high-frequency sounds (i.e., /AH/ and /SH/). Speech-in-noise testing revealed significant improvements pre- vs postoptimization, and participants were generally satisfied with the overall procedure. Conclusion These findings demonstrated that middle- and high-frequency tokens could be successfully optimized using CAEPs, resulting in significant improvements in hearing performance. Our results support the use of CAEPs for the optimization of aMEI and BCI adult users' fitting.