The use of cortical evoked response audiometry in the assessment of noise-induced hearing loss.
OBJECTIVE
The study aims were to determine the incidence of exaggerated hearing thresholds in individuals complaining of noise-induced hearing loss (NIHL) as a result of impulse noise using cortical evoked response audiometry (CERA) and to identify any associated audiometric features.


METHODS
We conducted an office-based study.


METHODS
In this prospective case series, 1154 males complaining of NIHL were assessed with pure tone audiometry; 673 had CERA. Pure tone averages (PTA) and hearing disability were calculated using the Irish and American Medical Association systems. A PTA of >10 dB worse than the CERA average was considered evidence of exaggerated thresholds.


RESULTS
The mean PTA was 33 dB. Seventy-two percent had a hearing disability of an average of 26% when assessed by the Irish system. Fifty-four percent had a hearing disability of an average of 30% when assessed by the American Medical Association system. Twenty-six percent of subjects had exaggerated thresholds based on CERA. A binaural hearing threshold of >25 dB at 500 Hz had a sensitivity of 94% and a specificity of 59% for the detection of exaggerated thresholds.


CONCLUSIONS
Exaggerated hearing thresholds are common. A hearing threshold of >25 dB at 500 Hz should be considered an indication for CERA testing.
Hone
Stephen W
SW
Department of Otolaryngology-Head and Neck Surgery, Beaumont Hospital. stephen-hone@uiowa.edu
Norman
Garry
G
Keogh
Ivan
I
Kelly
Vivian
V
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001301:Audiometry, Pure-Tone / Q000379:methods*; D001309:Auditory Threshold / Q000502:physiology; D004185:Disability Evaluation; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006317:Hearing Loss, Noise-Induced / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012720:Severity of Illness Index