Cochlear Implant Electrode Deactivation Produces Higher Individual but Lower Average Outcome Scores

Area of Science:

• Audiology
• Neurosurgery
• Biomedical Engineering

Background:

• Cochlear implantation (CI) is a vital auditory prosthesis for severe to profound hearing loss.
• Electrode array integrity is crucial for optimal CI function and speech perception.
• Electrode deactivation, a strategy to manage adverse effects, warrants further investigation.

Purpose of the Study:

• To compare cochlear implant (CI) performance in recipients with intact electrode arrays versus those with deactivated electrodes.
• To analyze the impact of electrode deactivation on speech perception outcomes, including aided thresholds and sentence recognition.

Main Methods:

• Retrospective review of adult CI recipients using the Advanced Bionics HiRes Mid-Scala electrode.
• Comparison of speech perception scores (AzBio) and aided thresholds between fully functioning and partially deactivated electrode arrays.
• Analysis of reasons for electrode deactivation and their correlation with outcomes.

Main Results:

• 29% of recipients had one or more deactivated electrodes, primarily due to sound quality concerns or lack of percept.
• Significant differences in aided thresholds were observed across most frequencies between the groups.
• Recipients with deactivated electrodes, especially for poor sound quality or incomplete insertion, showed significantly worse speech perception scores.

Conclusions:

• Electrode deactivation is a frequent clinical practice in cochlear implantation.
• While associated with lower average group speech perception, deactivation can lead to improved individual scores.
• Understanding the reasons for deactivation is critical for interpreting CI performance data.