Longitudinal Trends in Cochlear Implant Programming from a Single-Institution Review of Over 400 Adult Implant Recipients: Evidence to Support Selective De-Escalation of Device Programming.

Objective: To examine comfort (C) and threshold (T) levels in adult cochlear implant (CI) recipients over the first 18 months postactivation.

Study design: Retrospective review of longitudinal CI programming data.

Setting: Tertiary academic center.

Patients: A total of 480 CIs among 428 adult CI recipients.

Interventions: Cochlear implantation with Cochlear Ltd. devices with subsequent programming to behavioral standards using Custom Sound® fitting software.

Main outcome measures: Charge levels needed to achieve C and T levels were measured longitudinally using Custom Sound®, from time of activation to a minimum of 6 and a maximum of 18 months postactivation. Charge (nC) levels were calculated as the product of pulse width (μs) and current amplitude (μA) to standardize among implant models. Changes in C and T charge levels over time were evaluated using repeated-measures analysis of variance.

Results: When considering the entire electrode, the largest increases were seen at 1 month postactivation, and C and T charge levels did not increase significantly after 6 and 12 months, respectively. These findings were consistent across patient age at implantation and sex. When considering proximal electrodes only, C and T levels did not increase significantly after 6 months. In distal electrodes only, C levels did not increase significantly after 6 months, but T levels continued to demonstrate small, but statistically significant increases up to 18 months postactivation.

Conclusions: Across the entire electrode, we observed the largest changes in C and T charge levels at 1 month postactivation. Small increases in C and T levels continued out to 6 and 12 months, respectively, but may be of limited clinical significance. The stability of programming levels over time may support selective de-escalation of CI follow-up after the initial postactivation period, but, given small yet persistent increases with time, most notably in the distal electrodes, alternatives for follow-up or remote programming may still be encouraged.