Neural health in cochlear implant users with ipsilateral residual hearing

  • Marina Imsiecke Clinic for Laryngology, Rhinology and Otology, Hanover Medical School, Germany
  • Andreas Büchner Clinic for Laryngology, Rhinology and Otology, Hanover Medical School, Germany; Cluster of Excellence ’Hearing4All’, Hanover, Germany
  • Thomas Lenarz Clinic for Laryngology, Rhinology and Otology, Hanover Medical School, Germany; Cluster of Excellence ’Hearing4All’, Hanover, Germany
  • Waldo Nogueira Clinic for Laryngology, Rhinology and Otology, Hanover Medical School, Germany; Cluster of Excellence ’Hearing4All’, Hanover, Germany
Keywords: eCAP, AGF, Neural Health, Electric-acoustic stimulation

Abstract

Studies in cochlear implant (CI) users have shown a correlation between neural health and speech reception performance. Recently, electrically evoked compound action potentials (eCAP) with varying interphase gaps (IPG) have been used to estimate neural health. In the present study, we investigated eCAP characteristics in CI users with ipsilateral residual hearing (electric-acoustic stimulation, EAS). We hypothesized that neural health is better in apical areas in EAS users than in basal areas, due to increased hair cell survival. Amplitude growth functions (AGF) with varying IPGs of 2.1 and 10 μs were measured in 19 MED-EL Flex recipients with residual hearing. The eCAP characteristics slope, N1 latency and stimulus level at 50% maximum eCAP amplitude were investigated for the effect of IPG across electrode positions and were correlated to speech perception outcomes and duration of hearing loss. CI users without residual hearing were used as a control group to compare the patterns of slope, latency and 50% maximum amplitude between both IPGs. IPG showed a significant effect on the eCAP characteristics. The change in stimulus level for the 50% maximum amplitude showed a significant difference between electrode 1 and 3 as well as 1 and 4 in EAS users, maybe indicating impaired neural health in the medial region and validating the measurement in EAS users.

References

Gärtner, L., Lenarz, T., and Bu ̈chner, A. (2018). “Fine-grain recordings of the electrically evoked compound action potential amplitude growth function in cochlear implant recipients,” Biomed. Eng., 17(1), 140, doi: 10.1186/s12938- 018-0588-z.

Hochmair-Desoyer, I., Schulz, E., Moser, L., and Schmidt, M. (1997). “The HSM sentence test as a tool for evaluating the speech understanding in noise of cochlear implant users,” Am. J. Otol., 18(6), 83.

Holden, L., Finley, C., Firszt, J., Holden, T., Brenner, C., Potts, L., Gotter, B., Vanderhoof, S., Mispagel, K., Heydebrand, G. et al. (2013). “ Factors affecting open-set word recognition in adults with cochlear implants,” Ear Hear., 34(3), 342, doi: 10.1097/AUD.0b013e3182741aa7.

Nadol, J., Burgess, B., Gantz, B., Coker, N., Ketten, D., Kos, I., Roland, J., Shiao, J., Eddington, D., Montandon, P. et al. (2001). “ Histopathology of cochlear implants in humans,” Ann. Otol. Rhinol. Laryng., 110(9), 883–891.

Pfingst, B.E., Zhou, N., Colesa, D.J., Watts, M.M., Strahl, S.B., Garadat, S.N., Schvartz-Leyzac, K.C., Budenz, C.L., Raphael, Y. and Zwolan, T.A. (2015). “ Importance of cochlear health for implant function,” Hear. Res., 322, 77-88, doi: 10.1016/j.heares.2014.09.009.

Prado-Guitierrez, P., Fewster, L.M., Heasman, J.M., McKay, C.M., and Shepherd, R.K. (2006). “Effect of interphase gap and pulse duration on electrically evoked potentials is correlated with auditory nerve survival,” Hear. Res., 215, 47-55, doi: 10.1016/j.heares.2006.03.006.

Ramekers, D., Versnel, H., Strahl, S.B., Smeets, E.M., Klis, S.F.L., and Grolman, W. (2014). “Auditory-nerve responses to varied inter-phase gap and phase duration of the electric pulse stimulus as predictors for neuronal degeneration,” J. Assoc. Res. Oto., 15(2), 187-202, doi: 10.1007/s10162-013-0440-x.

Schvartz-Leyzac, K.C., and Pfingst, B.E. (2018). “Assessing the Relationship Between the Electrically Evoked Compound Action Potential and Speech Recognition Abilities in Bilateral Cochlear Implant Recipients,” Ear Hearing, 39(2), 344-358, doi: 10.1097/AUD.0000000000000490.

Seyyedi, M., Viana, L.M. and Nadol, J.B. (2014). “ Within-subject comparison of word recognition and spiral ganglion cell count in bilateral cochlear implant re- cipients,” Otol. Neurotol., 35(8), 1446, doi: 10.1097/MAO.0000000000000443.

Wagener, K., Ku ̈hnel, V., and Kollmeier, B. (1999). “Development and evaluation of a German sentence test I: Design of the Oldenburg sentence test,” Zeitschrift Fu ̈r Audiologie, 38, 4-15.

Published
2020-04-24
How to Cite
Imsiecke, M., Büchner, A., Lenarz, T., & Nogueira, W. (2020). Neural health in cochlear implant users with ipsilateral residual hearing. Proceedings of the International Symposium on Auditory and Audiological Research, 7, 21-28. Retrieved from https://proceedings.isaar.eu/index.php/isaarproc/article/view/2019-03
Section
2019/1. Auditory precision medicine