gms | German Medical Science

Fourth International Symposium and Workshops: Objective Measures in Cochlear Implants

Medical University of Hannover

01.06. bis 04.06.2005, Hannover

Frequency-specific objective audiometry: tone-evoked brainstem responses and 40 Hz and 90 Hz steady-state potentials

Meeting Abstract

Suche in Medline nach

  • corresponding author C.S. van der Reijden - Department of Otorhinolaryngology, University Medical Centre Nijmegen
  • L.H.M. Mens - Department of Otorhinolaryngology, University Medical Centre Nijmegen
  • A.F.M. Snik - Department of Otorhinolaryngology, University Medical Centre Nijmegen

Medical University of Hannover, Department of Otolaryngology. Fourth International Symposium and Workshops: Objective Measures in Cochlear Implants. Hannover, 01.-04.06.2005. Düsseldorf, Köln: German Medical Science; 2005. Doc05omci003

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/omci2005/05omci003.shtml

Veröffentlicht: 31. Mai 2005

© 2005 van der Reijden et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielfältigt, verbreitet und öffentlich zugänglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Introduction

Auditory Brainstem Responses evoked with tone bursts (t-ABRs) and Auditory Steady-State Responses (ASSRs) with 40 or 90 Hz amplitude modulation (AM) were compared to determine which method most accurately approached the behavioural hearing thresholds to 500 and 2000 Hz stimuli in awake adults with normal hearing.

Materials and Methods

This study was unique because identical measurement parameters were used for both methods (viz. recording time, stimulation and recording hardware and electrode positions). Measurements were performed in quasi-random order; presentation levels were in dB SL. Ten normal hearing adults participated in the measurements.

Results

ASSR thresholds at 40 and 90 Hz AM approached the behavioural thresholds more accurately than the t-ABR thresholds for 500 and 2000 Hz. E.g. the estimated thresholds and standard deviations were measured from ASSRs with 40 Hz AM stimuli: 13 dB SL (S.D. 7 dB) at 500 Hz and 12 dB SL (S.D. 4 dB) at 2000 Hz. Average thresholds with the t-ABR were 27 dB SL (S.D. 10 dB) at 500 Hz tones and 18 dB SL (S.D. 8 dB) at 2000 Hz. Results from ASSRs with 90 Hz AM stimuli were in between.

Conclusions

It is concluded that when measurement conditions are kept the same (as far as possible), the ASSR with 40 Hz AM is the best choice while t-ABR gave the poorest results.