Investigation of the effect of sequential cochlear implant application on the most comfy sensory level, impedance and electrical compound action potential measurement results in the first cochlear implant in children

The aim of this study was to investigate the effect of second cochlear implant application on the first cochlear implant application in consecutive cochlear implant applications in terms of impedance, the most comfortable hearing level and electrical compound action potential. This study was carried out with a total of 30 children (12 girls (40%) and 18 boys (60%). The ages of children change between 15 and 144 months. After the first cochlear implant, the children who received cochlear implants for at least 3 months were included in the study. Impedance, ECAP and M levels were evaluated while the second cochlear implants of all children were open and closed. When the second cochlear implant was activated, impedance measurements of the first implant were statistically significant only at 1 month. When the second cochlear implant was activated, a statistically significant difference was found at the 1st month, 3rd month and 6th month of ECAP and M levels of the first implant (p <0.05). There is no change in impedance, ECAP and M levels of the first cochlear implant compared to the values before the CI2 operation when the second cochlear implant is closed in a sequential cochlear implant. However, with the activation of the second cochlear implant, changes in impedance, ECAP and M levels occur in the first cochlear implant. After the activation of the second cochlear implant, the control of both the first cochlear implant and the second cochlear implant impedance values, ECAP, M levels and the dynamic range are necessary for the patient's auditory performance.