gms | German Medical Science

80th Annual Meeting of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery

German Society of Oto-Rhino-Laryngology, Head and Neck Surgery

20.05. - 24.05.2009, Rostock

Experimental study concerning the effect of positive Gz – acceleration on human hearing

Meeting Abstract

  • corresponding author Michael Kuehn - German Air Force Institute of Aviation Medicine, Division Aviation Physiology, Königsbrück, Germany
  • Matthias Bornitz - TU Dresden, Department of Medicine, Clinic of Otorhinolaryngology, Dresden, Germany
  • Yury Yarin - TU Dresden, Department of Medicine, Clinic of Otorhinolaryngology, Dresden, Germany
  • Achim Knobloch - German Air Force Institute of Aviation Medicine, Division Aviation Physiology, Königsbrück, Germany
  • Peter Lindner - German Air Force Institute of Aviation Medicine, Division Aviation Physiology, Königsbrück, Germany
  • Dirk Mürbe - TU Dresden, Department of Medicine, Clinic of Otorhinolaryngology, Dresden, Germany
  • Michael Nehring - German Air Force Institute of Aviation Medicine, Division Aviation Physiology, Königsbrück, Germany
  • Bernd Brix - German Air Force Institute of Aviation Medicine, Division Aviation Physiology, Königsbrück, Germany
  • Thomas Zahnert - TU Dresden, Department of Medicine, Clinic of Otorhinolaryngology, Dresden, Germany

German Society of Oto-Rhino-Laryngology, Head and Neck Surgery. 80th Annual Meeting of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery. Rostock, 20.-24.05.2009. Düsseldorf: German Medical Science GMS Publishing House; 2009. Doc09hno080

doi: 10.3205/09hno080, urn:nbn:de:0183-09hno0803

Published: July 22, 2009

© 2009 Kuehn 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

Background: Decreased blood flow and stagnant hypoxia are discussed to be main reasons for inner ear dysfunction, especially for a few types of sudden hearing loss (SHL) and noise induced hearing loss (NHL).Several types of hypoxia cause impairment of inner ear function [1], [2]. Changes of the DPOAE-signal are observed,

but only after centrifuge runs [3]. This pilot study was aimed to find out if acceleration and stagnant hypoxia affect human hearing.

Methods: Using the high performance human centrifuge of the German Airforce Institute of Aviation Medicine, Distortion Product Otoacoustic Emissions (DPOAE) from 1 kHz to 4 kHz (f2) and eardrum impedance of 8 male volunteers were recorded during centrifuge runs with increasing acceleration up to +5 Gz (z-axis, head to foot).

Results: During increased positive acceleration starting at 3 g about 5–10 dB decreased DPOAE were observed at all frequencies of 8 male volunteers. DPOAE amplitudes were more reduced in the lower (1–2 kHz) than in the higher frequency range (3–4 kHz). Additionally eardrum impedance also increased with increasing acceleration.

Conclusions: Inner and middle ear function are affected by positive acceleration (z-axis, head to foot). To distinguish between perfusion and mechanical caused impairment of hearing further research is necessary. The effect of decreased cerebral perfusion might be compensated by anti-G-suits.


References

1.
Ze Dong J, Zhang Z, Wilkinson AR. Distortion product otoacoustic emissions in term infants after hypoxia-ischaemia. Eur J Pediatr. 2005;164:84-7.
2.
Mess K, Behnisch A, Suckfüll M. Audimont – eine wissenschaftliche Expedition zum Cho Oyu im Himalaya. Fortschritte in der Medizin-Orginalien. 2003;121(1):2003:1-4.
3.
Johnson RE, Allen JR, Schultz T, Liening DA, Bell AF. The Effects of Linear Acceleration on Distortion Product Otoacoustic Emissions in Human Ears. Avat Space Envir Med. 1998;69(1):40-4.