Conventional Audiometry, Extended High-Frequency Audiometry, and DPOAE for Early Diagnosis of NIHL.
BACKGROUND
Noise most frequently affects hearing system, as it may typically cause a bilateral, progressive sensorineural hearing loss at high frequencies.


OBJECTIVE
This study was designed to compare three different methods to evaluate noise-induced hearing loss (conventional audiometry, high-frequency audiometry, and distortion product otoacoustic emission).


METHODS
This was a cross-sectional study. Data was analyzed by SPSS (ver. 19) using chi square, T test and repeated measures analysis. Study samples were workers from tile and ceramic industry.


RESULTS
We found that conventional audiometry, extended high-frequency audiometry, low-tone distortion product otoacoustic emission and high-tone distortion product otoacoustic emission had abnormal findings in 29 %, 69 %, 22 %, and 52 % of participants. Most frequently affected frequencies were 4000 and 6000Hz in conventional audiometry, and 14000 and 16000 in extended high-frequency audiometry.


CONCLUSIONS
Extended high-frequency audiometry was the most sensitive test for detection of hearing loss in workers exposed to hazardous noise compared with conventional audiometry and distortion product otoacoustic.
Department of Occupational Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran.
Amir Houshang
AH
Mehrparvar
Department of Occupational Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran.
Seyyed Jalil
SJ
Mirmohammadi
Department of Occupational Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran.
Mohammad Hossein
MH
Davari
Department of Occupational Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran.
Mehrdad
M
Mostaghaci
Industrial Diseases Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran.
Abolfazl
A
Mollasadeghi
Industrial Diseases Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran.
Maryam
M
Bahaloo
Department of Occupational Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran.
Seyyed Hesam
SH
Hashemi
Audiometry; Hearing Loss; Noise; Otoacoustic Emissions, Spontaneous