Predicting hearing thresholds and occupational hearing loss with multiple-frequency auditory steady-state responses.
OBJECTIVE
An objective investigation is needed to verify the existence and severity of hearing impairments resulting from work-related, noise-induced hearing loss in arbitration of medicolegal aspects. We investigated the accuracy of multiple-frequency auditory steady-state responses (Mf-ASSRs) between subjects with sensorineural hearing loss (SNHL) with and without occupational noise exposure.


METHODS
Cross-sectional study.


METHODS
Tertiary referral medical centre.


METHODS
Pure-tone audiometry and Mf-ASSRs were recorded in 88 subjects (34 patients had occupational noise-induced hearing loss [NIHL], 36 patients had SNHL without noise exposure, and 18 volunteers were normal controls).


METHODS
Inter- and intragroup comparisons were made. A predicting equation was derived using multiple linear regression analysis.


RESULTS
ASSRs and pure-tone thresholds (PTTs) showed a strong correlation for all subjects (r = .77 ≈ .94). The relationship is demonstrated by the equationThe differences between the ASSR and PTT were significantly higher for the NIHL group than for the subjects with non-noise-induced SNHL (p < .001).


CONCLUSIONS
Mf-ASSR is a promising tool for objectively evaluating hearing thresholds. Predictive value may be lower in subjects with occupational hearing loss. Regardless of carrier frequencies, the severity of hearing loss affects the steady-state response. Moreover, the ASSR may assist in detecting noise-induced injury of the auditory pathway. A multiple linear regression equation to accurately predict thresholds was shown that takes into consideration all effect factors.
Hsu
Ruey-Fen
RF
Departments of Otolaryngology and Occupational Medicine, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
Ho
Chi-Kung
CK
Lu
Sheng-Nan
SN
Chen
Shun-Sheng
SS
D000161:Acoustic Stimulation / Q000379:methods*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001301:Audiometry, Pure-Tone; D001306:Auditory Pathways / Q000503:physiopathology*; D001309:Auditory Threshold / Q000502:physiology*; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006317:Hearing Loss, Noise-Induced / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009623:Noise, Occupational / Q000009:adverse effects*; D009784:Occupational Diseases / Q000175:diagnosis* / Q000503:physiopathology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012720:Severity of Illness Index; D055815:Young Adult