Changes in Intraoperative and Postoperative Neural Response Telemetry in Cochlear Implant Users

Youssif, Mostafa A.; Abd Al-Ghaffar, Mohamed; A. Moussa, Shahenda

doi:10.21608/ejnso.2018.57892

Changes in Intraoperative and Postoperative Neural Response Telemetry in Cochlear Implant Users

Authors

10.21608/ejnso.2018.57892

Abstract

Introduction: The cochlear implant directly stimulates the auditory nerve in deaf patients. Neural Response Telemetry (NRT) is used to record the response of the auditory nerve through the feedback of the electrical signal. NRT does not need behavioral responses from very young children for thresholds and comfort levels. This study was conducted to detect the changes in intraoperative and postoperative neural response telemetry in cochlear implant users.
Patients and Methods: Thirty patients were implanted with a MED-EL device, Sonata II, at Sohag University hospital. The neural responses of electrodes 2, 4, 6, 8, 9, 10, 11 and 12 were investigated intraoperatively, one month and 3 months postoperativly. Threshold of the neuronal response is calculated using linear equation function.
Results: There is significant improvement in thresholds of NRT response postoperatively which were elevated or absent in intraoperative measurement. NRT threshold increases again in 3 months postoperative follow up in comparison with first postoperative measurement but this increase is not statistically significant.
Conclusion: Absence or elevation of NRT response in some electrodes intraoperative does not mean that electrode must be out of function or outside the cochlea, and improvement usually happens postoperatively.

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