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Fourth International Symposium and Workshops: Objective Measures in Cochlear Implants

Medical University of Hannover

01.06. bis 04.06.2005, Hannover

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Advanced telemetry capabilities of the PULSARci100 cochlear implant

Meeting Abstract

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  • corresponding author H. Schößer - Med-El Medical Electronics, Worldwide Headquarters, Innsbruck, Austria
  • K. Veekmans - Med-El Medical Electronics, Worldwide Headquarters, Innsbruck, Austria
  • P. Spitzer - Institute of Applied Physics, University of Innsbruck, Austria
  • C.M. Zierhofer - Institute of Applied Physics, University of Innsbruck, Austria

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. Doc05omci030

The electronic version of this article is the complete one and can be found online at: http://www.egms.de/en/meetings/omci2005/05omci030.shtml

Published: May 31, 2005

© 2005 Schößer et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.

Outline

Text

Introduction

The level of speech intelligibility that can be reached with cochlear implants depends, among other parameters, on patient specific speech processor settings. Thresholds and maximum stimulation levels have to be found. To simplify the fitting procedure as well as for research purposes and to prove the correct functioning of the implant under special circumstances the use of objective measures might be helpful.

Materials and Methods

Besides the Impedance and Field Telemetry (IFT) known from the COMBI 40+ system, the precision IFT of the PULSARci100 provides four different gains for even more accurate information. In addition to that the Auditory Nerve Response Telemetry (ART) offers the possibility of recording the Electrically Evoked Compound Action Potential (ECAP) of the auditory nerve. Both functionalities are based on ΣΔ modulation at 1.2 MHz, for the digitalization of the signal.

Results

An internal RAM with short readout time allows the storage of the digitized signal within a time window of about 1.7ms. In the ECAP-recording mode this measurement window can be moved to any position of interest. For the amplification of the very small ECAP-signals ART uses an optimized single state blanking amplifier with a fixed gain of 100. Also the ΣΔ- modulator offers an additional signal amplification.

Conclusions

Besides the use of various test signal for an objective evaluation first experiences with the telemetry capabilities of the PULSARci100 have been gathered in real test situation at patients.