Comparison of auditory steady-state responses and auditory brainstem responses in audiometric assessment of adults with sensorineural hearing loss.
OBJECTIVE
Many of the medico-legal patients who claimed compensation may exaggerate hearing loss that varies in degree, nature, and laterality. The purpose of this study was to investigate whether Auditory Steady-State Response (ASSR) could be used to predict the hearing level of adults, and whether ASSR could become a better testing method than Auditory brainstem response (ABR) in audiometric assessment of adults with sensorineural hearing loss.


METHODS
This was a prospective study, which was conducted in a tertiary referral hospital. From January to June 2007, 142 subjects (284 ears) with varying degrees of sensori-neural hearing impairment were included in this study. Four commonly used frequencies (500, 1000, 2000, 4000Hz) were evaluated. All subjects received pure-tone audiometry, multi-channel ASSR, and ABR tests for threshold measurement. The correlation of pure tone thresholds with ASSR and ABR thresholds were assessed.


RESULTS
Between multi-channel ASSR and pure tone thresholds, a difference of less than 15dB was found in 71% while a difference of less than 25dB was found in 89% of patients. The correlation coefficient (r) of multi-channel ASSR and pure tone thresholds were 0.89, 0.95, 0.96, and 0.97 at 500, 1000, 2000, and 4000Hz, respectively. The strength of the relationship increased with increasing frequency. On the other hand, between ABR and pure-tone thresholds, a difference of less than 15dB was found in 31%; a difference of less than 25dB was found in 62% of patients. The r correlation value for ABR and pure tone thresholds was 0.83.


CONCLUSIONS
ASSR is a more reliable test for the accurate prediction of auditory thresholds than ABR. It can be a powerful and convenient electro-physiologic examination tool for clinically assessing of adults with sensorineural hearing loss.
Lin
Yu-Hsing
YH
Department of Otolaryngology, Buddhist Dalin Tzu Chi General Hospital, Chiayi, Taiwan.
Ho
Hsu-Chueh
HC
Wu
Hung-Pin
HP
D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001300:Audiometry, Evoked Response; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold / Q000502:physiology; D001933:Brain Stem / Q000503:physiopathology*; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D013018:Sound Spectrography; D055815:Young Adult