Objectives: To describe the influence of stimulus parameters on aberrant facial nerve stimulation in cochlear implant users.
Methods: Retrospective case series (three ears - two patients). Cochlear implant patients with severe facial nerve stimulation and degraded speech comprehension who underwent re-implantation with Neuro Zti EVO (Oticon Medical).
Results: In all three ears, side effects evoked by aberrant facial nerve stimulation could be resolved and thereby speech comprehension was improved.
Conclusions: Aberrant facial nerve stimulation in cochlear implant patients was successfully resolved by re-implantation. We hypothesize that one or more of the specific stimulus paramet ers are responsible for this success: combined common ground and monopolar stimulation mode, asymmetric pulse waveform with active anodic leading first phase followed by slow capacitive discharge, and pulse width modulation for loudness coding.
Keywords: Facial nerve; cochlear implant; combined stimulation mode; loudness coding; pulse waveform; speech intelligibility.