[Registration of evoked otoacoustic emission in the members of locomotive crews of the railroad service].

The objective of the present study was to evaluate characteristics of the hearing function in the subjects exposed to intense occupational noise. The audiologic examination involved members of locomotive crews of the railroad transport and included impedancometry, threshold tonal audiometry, and registration of two types of evoked otoacoustic emission (delayed evoked otoacoustic emission and distortion product otoacoustic emission). Characteristics of otoacoustic emission in subjects with occupational loss of hearing were compared with those in patients with neurosensory deafness of a different etiology. It was shown that registration of different classes of evoked otoacoustic emission makes it possible to recognize early pre-clinical signs of inner ear disorders caused by intense occupational noise. The changes are first and foremost apparent within a frequency band of 4 kHz. At the same time, registration of individual types of evoked otoacoustic emission does not permit to differentiate between occupational loss of hearing and neurosensory deafness of other origin.