title: Assessment of the central hearing system of sport divers.
abstract: OBJECTIVE
  To investigate the effect of regular scuba diving on central processing sequences of sport divers who have no history of noise exposure or ear-related accidents using a comprehensive topographic examination of the central hearing system.
  
  
  METHODS
  Cross-sectional controlled comparison study.
  
  
  METHODS
  General sports diving community.
  
  
  METHODS
  81 sport divers with a mean of 300 dives each were compared with a control group of 81 non-divers.
  
  
  METHODS
  The participants were classified into three age groups. Hearing test results were combined for both ears. Examination included brainstem evoked response audiometry (BERA), cortical evoked response audiometry (CERA) and dichotic listening tests to screen for retrocochlear and central hearing disorders. Testing of brainstem latencies was performed in a gender-dependent manner.
  
  
  RESULTS
  BERA showed a pathological extension of the I-V-latency in one diver. Magnetic tomographic imaging ruled out brainstem lesions. No reason for the measured latency could be detected. All other latencies (I-III, III-V and I-V) in both gender groups were within normal limits. No statistically significant differences between divers and non-divers could be detected. Dichotic listening showed no clinical abnormalities in any of the participants, but in the age group 18-29 years divers performed significantly better than non-divers (p = 0.01). CERA revealed no significant differences between divers and non-divers in the age group 18-29 years and 30-39 years, whereas divers in the age group 41-50 demonstrated significantly better test results (p = 0.045) (difference of the means: 4.18 dB).
  
  
  CONCLUSIONS
  Dichotic listening and CERA did not reveal a significant reduction of central hearing performance in divers. Persistent on-shore BERA wave latency prolongations that were present in one study could not be confirmed in our study group. This first comprehensive topographic examination of the central hearing system of divers showed no abnormalities.
authors.affiliation: Department for Otorhinolaryngology and Head & Neck Surgery, University of Heidelberg, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Hausmann
authors.forename: S
authors.initials: S
authors.lastname: Laabling
authors.forename: S
authors.initials: S
authors.lastname: Hoth
authors.forename: P K
authors.initials: PK
authors.lastname: Plinkert
authors.forename: C
authors.initials: C
authors.lastname: Klingmann
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001300:Audiometry, Evoked Response / Q000379:methods; D001309:Auditory Threshold / Q000502:physiology; D003430:Cross-Sectional Studies; D004007:Dichotic Listening Tests / Q000379:methods; D004242:Diving / Q000009:adverse effects* / Q000502:physiology; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D005260:Female; D006309:Hearing / Q000502:physiology*; D034381:Hearing Loss / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult