Impact of Two Visualization Methods for Electrocochleographic Potentials on Hearing and Vestibular Function During Cochlear Implantation.

Purpose: This study investigates the impact of two distinct visualization methods for electrocochleographic potentials during cochlear implant electrode insertion on residual hearing preservation and vestibular function. Previous research has demonstrated the benefits of visualizing electrocochleographic (ECochG) potentials in preserving residual hearing during cochlear implantation. In this project, ECochG potentials are represented either through a graph or as arrows that provide a pre-interpreted version of the graph. We aim to determine if these visualization methods influence postoperative residual hearing and vestibular structure integrity.

Methods: Residual hearing is audiometrically assessed, and vestibular function is evaluated using the video head impulse test and the dizziness handicap inventory before and after surgery. Furthermore, the subjective workload of surgeons using these methods is assessed via the NASA-Task Load Index questionnaire. The study included 31 patients receiving Flex26 and Flex28 electrodes (MED EL). The patients were randomly assigned to one of the visualization methods.

Results: The results of the study demonstrate that there were no significant differences between the two visualization methods, both in terms of residual hearing preservation and postoperative dizziness. Also the ECochG parameters, such as amplitude, do not differ significantly. Additionally, no significant difference was observed in the surgical workload for the operating surgeon.

Conclusion: The two visualization methods can therefore be used equivalently in terms of preservation of cochlear structures and mental workload for the surgeons. A simplified ECochG potential interpretation could enable younger surgeons to perform more atraumatic insertions with stable quality of outcome.