High-frequency audiometry in normal hearing military firemen exposed to noise

Braz J Otorhinolaryngol. 2010 Nov-Dec;76(6):687-94. doi: 10.1590/S1808-86942010000600003.

Abstract

The study of high frequencies has proven its importance for detecting inner ear damage. In some cases, conventional frequencies are not sensitive enough to pick up early changes to the inner ear.

Aim: To analyze the results of threshold high frequency analysis of individuals exposed to noise with normal conventional audiometry.

Materials and methods: This was a retrospective cross-sectional cohort study, in which we studied 47 firefighters of the Fire Department of Rio de Janeiro, based on Santos Dumont airport and 33 military men without noise exposure. They were broken down into two age groups: 30-39years and 40-49years. The high frequencies were studied immediately after conventional audiometry.

Results: The results were most significant in the 40 to 49 years of age range, where the experimental group showed significantly higher threshold values than the control group 14000Hz (p = 0.008) and 16,000Hz (p = 0.0001).

Conclusions: We concluded that noise interfered with high frequency thresholds, where all the mean values found in the experimental group were higher than those in the control group. We suggest that these data reinforce the importance of studying high frequencies, even with normal conventional audiometry in the early detection of noise-induced hearing loss.

MeSH terms

  • Adult
  • Age Factors
  • Audiometry / methods*
  • Auditory Threshold / physiology*
  • Case-Control Studies
  • Cohort Studies
  • Ear / physiopathology
  • Hearing Loss, High-Frequency / diagnosis*
  • Humans
  • Male
  • Middle Aged
  • Military Personnel*
  • Noise, Occupational / adverse effects*
  • Occupational Health
  • Retrospective Studies
  • Statistics, Nonparametric
  • Time Factors