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. 2019 Dec;14(4):128-135.
doi: 10.1016/j.joto.2019.06.002. Epub 2019 Jun 28.

Efficacy of using NRT thresholds in cochlear implants fitting, in prelingual pediatric patients

Ahmed Allam  1 , Ahmed Eldegwi  1
Affiliations

Efficacy of using NRT thresholds in cochlear implants fitting, in prelingual pediatric patients

Ahmed Allam et al. J Otol. 2019 Dec.

Abstract

Objective: To evaluate the efficacy of using neural response telemetry (NRT) thresholds in predicting behavioural thresholds during programming of cochlear implant in prelingual children.

Method: Prospective study of 28 cochlear implants implanted with Nucleus 24 cochlear implant. We recorded NRT-thresholds on electrode numbers 1, 6, 11, 16 and 22 of the electrode array in each patient, the neural response thresholds were correlated with the behavioural map after six months of programming the device.

Results: The mean neural response telemetry level was significantly higher than the mean threshold level (T-level) but lower than the comfortable level (C-level) in all the electrodes tested. NRT levels could statistically significantly predict T behavioural levels and comfortable behavioural levels, p < 0.01. There was a strong positive correlation between comfortable thresholds and neural response telemetry level measurements and behavioural threshold level and neural response telemetry threshold measurements.

Conclusion: There is a useful role for neural response telemetry values in predicting the behavioural threshold and comfortable values in prelingual children. Combining the NRT values with behavioural observations can improve the programming of cochlear implants.

Keywords: Behavioural levels; Cochlear implant; ECAP; NRT; Programming.

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Figures

Fig. 1
Fig. 1
Custom Sound program EP 3.2 showing Auto-NRT with parameters and curves used for recording the NRT threshold.
Fig. 2
Fig. 2
The intraoperative NRT thresholds (μV) recorded on electrode numbers 22, 16, 11, 6 and 1 in one of the studied cases.
Fig. 3
Fig. 3
A map from one of the studied cases done 6 months after implantation. Comfortable levels (C) (red marks) and threshold levels (T) (green marks) in the selected electrode numbers 22, 16, 11, 6 and 1. DR represents the dynamic range.
Fig. 4
Fig. 4
The relationship between mean values of neural rResponse telemetry thresholds and threshold and comfortable levels on the different electrodes.
Fig. 5
Fig. 5
Correlation between NRT level and C-level (regression).
Fig. 6
Fig. 6
Correlation between neural response telemetry level and threshold level (regression).
Fig. 7
Fig. 7
Bland–Altman plot of the association between neural response telemetry level and comfortable level.
Fig. 8
Fig. 8
Bland–Altman plot of the association between neural response telemetry level and threshold level.
Fig. 9
Fig. 9
Mountain plots corresponding to Fig. 7, plot C, and (Mittal and Panwar, 2009), plot D.
See this image and copyright information in PMC

References

    1. Brown C.J., Hughes M.L., Luk B., Abbas P.J., Wolaver A., Gervais J. The relationship between EAP and EABR thresholds and levels used to program the nucleus 24 speech processor: data from adults. Ear Hear. 2000;21(2):151–163. - PubMed
    1. Cafarelli Dees D., Dillier N., Lai W., Von Wallenberg E., Van Dijk B., Akdas F. Normative findings of electrically evoked compound action potential measurements using the neural response telemetry of the Nucleus CI24M cochlear implant system. Audiology and Neurotology. 2005;10(2):105–116. - PubMed
    1. Chen X., Han D., Zhao X., Wang S., Kong Y., Liu S. [Comparison of neural response telemetry thresholds with behavioral T/C levels] Zhonghua Er Bi Yan Hou Ke Za Zhi. 2002;37(6):435–439. - PubMed
    1. Cullington H. Preliminary neural response telemetry results. Br. J. Audiol. 2000;34(3):131–140. - PubMed
    1. De Vos J.J., Biesheuvel J.D., Briaire J.J., Boot P.S., van Gendt M.J., Dekkers O.M. Use of electrically evoked compound action potentials for cochlear implant fitting: a systematic review. Ear Hear. 2018;39(3):401–411. - PubMed