title: [The influence of short-term pure tone exposure on amplitude of distortion-product otoacoustic emissions and spectral history].
abstract: OBJECTIVE
  To observe the changs of the amplitude and the spectral history of DPOAE in the slightly damaged cochlea.
  
  
  METHODS
  Fifteen of young person with normal hearing were exposed to 4 kHz short-term pure tone (Level = 130 dB SPL) for 3 minutes to analysis the change of DPOAE in details after Temporary Threshold Shift (TTS).
  
  
  RESULTS
  The comparison of pre- and postexposure showed that the thresholds of sound reflex is 9.78 +/- 6.98, 8.04 +/- 5.58, 13.0 +/- 5.58 dB HL and 8.82 +/- 6.23, 5.75 +/- 4.42, 9.05 +/- 2.27 dB HL in 0.5, 1, 2 kHz, respectively. The amplitude of DPOAE decreased 4.28 dB SPL in 6 kHz, and the spectral history rippled significantly. The coefficience of variance is 5.18 +/- 1.63%. The combination of the amplitude and the coefficience of variance indicated that 80.0% of those is abnormal.
  
  
  CONCLUSIONS
  The results confirmed that the spectral history of DPOAE is a sensible tool to assess the slightly cochlear lesion together with the amplitude of DPOAE.
authors.affiliation: Union Hospital, Tongji Medical University, Wuhan 430022.
authors.forename: H
authors.initials: H
authors.lastname: Li
authors.forename: N
authors.initials: N
authors.lastname: Zhong
mesh_terms: D000293:Adolescent; D000328:Adult; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold / Q000502:physiology*; D003051:Cochlea / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*