Patient Directed Basal Electrode Deactivation Is Associated with
Diminished Audibility
Abstract
Introduction: Cochlear implantation (CI) has revolutionized
patient care, however speech and audibility outcomes vary between
recipients. This study evaluates post-operative CI performance in
recipients with an intact electrode array compared to a smaller subset
with one or more basal electrodes deactivated to ascertain any
significant differences in speech perception. Methods: A
retrospective review of a single CI centre database (from 2011-2021) in
[BLINDED], using a Mid-Scala electrode, with focus on recipients
identified with one or more deactivated basal electrodes was performed.
Comparisons between conventional users and the deactivated cohort
included aided pure tone testing in sound field and open-set sentence
recognition scores (AzBio) at one-year post activation. Subjective
measures were collected to assess overall satisfaction with devices.
Results: 48 individuals out of 167 adult recipients had
selected for deactivation of basal electrodes. Reasons for deactivation
included sound quality and lack of sound percept. There were no
significant differences in pre-operative status or demographics between
the two cohorts. T-Test analysis found significant differences in aided
thresholds between the “intact” and “deactivated” electrode cohorts
at 4KHz and 6KHz (p <0.01). Mean post-operative speech
perception was also significantly worse in the “deactivated” cohort
(48.5% compared to 59.0%) at 1-year post activation
(p<0.01). There were no significant differences found between
groups in overall satisfaction with their CI. Conclusion:
Patient request for basal electrode deactivation owing to subjective
sound quality illustrates decreased audibility and speech perception,
however CI satisfaction is preserved.