ECAP correlation with speech recognition performance - new predictory function in rehabilitation of cochlear implant recipients?

Abstract

<b>Introduction:</b> Despite well-established qualification criteria and pre-operation tests, there is still uncertainty about post-implantation performance in CI patients. One of the most interesting factors that affect the outcome is the survivability and function of cochlear nerve endings. ECAP (Evoked Compound Action Potential) is one of the tools that might be useful in the prediction of rehabilitation outcomes. Speech audiometry is one of the most commonly used and established performance tests. The study hypothesis is that there might be a correlation between ECAP values and speech audiometry results obtained over time.<b>Aim:</b> The aim was to check if changes within postop ECAP values correspond tochanges in speech intelligibility.<b>Materials and methods:</b> The study was designed as a retrospective observational one. Data was evaluated on a selected group of patients, with no blinding or control group. The study group consisted of 25 adult cochlear implant recipients, all with Cochlear devices, implanted at the Department of Otolaryngology of the Medical University of Bialystok, Poland, between 2016 and 2020. Data included ECAP measurements and speech audiometry results obtained during the first year of rehabilitation. The statistical analysis of the significance of data change over time and its correlation was performed.<b>Results:</b> Change of data over time was significant (P<0.05) for almost all data groups but it did not translates to the correlation of speech and ECAP.<b>Conclusions:</b> There is no statistically confirmed evidence suggesting that obtaining speech intelligibility is connected with change in ECAP values, which requires further research.