Evaluation of Noise-Induced Hearing Loss with Audiometer and Distortion Product Otoacoustic Emissions
Viraporn Atchariyasathian MD*, Satit Chayarpham MA*, Suchada Saekhow MD**
Affiliation : * Department of Otorhinolaryngology, Faculty of Medicine, Prince of Songkla University, Songkhla ** Department of Otorhinolaryngology, WattanaPat Hospital, Trang
Objective : To compare the results of audiogram and distortion product otoacoustic emissions (DPOAEs)
parameters between staffs working in a noisy environment and normal subjects.
Material and Method: Hearing function of 32 noise-exposed workers and 18 reference subjects were assessed
with DPOAEs and pure-tone audiometry. Results were compared among three groups: 1) ears of reference
subjects, 2) audiometrically normal ears of noise-exposed subjects, and 3) audiometrically abnormal ears of
noise-exposed subjects.
Results : DPOAEs parameters, statistically significant difference were found between group 1 and 2 and group
1 and 3 at all frequencies. Statistically significant differences in pass rate for DPOAEs at 4-6 kilohertz (kHz)
were also found between group 1 and 2.
Conclusion : DPOAEs are more sensitive than audiometry to detect pre-symptomatic inner ear damage. It may
play a role as screening and monitoring test for noise-exposed workers.
Keywords : Otoacoustic emissions, Occupational health
