[Usefulness of impedance audiometry in the objective evaluation of occupational hearing loss]

243 workers occupationally exposed to noise have been examined by pure tone audiometry and impedance audiometry. Hearing disturbance have been diagnosed in 145 cases (62%). Impedance audiometry was performed in 74 subjects. In 47 cases (70%) hearing thresholds were found consistent in both methods whereas the other 21 cases (30%) showed different hearing thresholds. Thirteen individuals of that group exhibited hearing impairment in the cochlea. Hearing loss has been simulated in two cases. The Lüscher-Zawisłocki test revealed 1-1.5 dB in all cases. Objective verification of loudness recruitment phenomenon allowed to state cochlear hearing localization in 31 cases.