NRT test in auditory neuropathy patients with cochlear implants

Abstract

Conclusion: In patients with auditory neuropathy (AN), waveforms of neural response telemetry (NRT) could be present, showing characteristics of low incidence, low differentiation, and large variation. Objective: To study the characteristics of NRT in AN patients who had received cochlear implants (CIs). Methods: NRT data for seven AN patients who had received Nucleus CIs were retrospectively analyzed. Twenty-one CI implantees with sensorineural hearing loss (SNHL) were included as the control group. The incidence of electrically evoked compound action potentials (ECAPs), threshold of wave N1, and amplitude of N1-P2 in the AN group were analyzed and compared between groups. Results: The intraoperative incidence of valid ECAPs in the AN group was 42.9%, and the postoperative incidence was 66.7%, both of which were lower than those in the SNHL group, which were 95.2% and 100%, respectively. NRT in the AN group showed larger variation and lower differentiation than in the SNHL group. Wilcoxon’s non-parametric test results indicated no significant difference between AN and SNHL groups in either the threshold of ECAP or N1-P2 amplitude.