[Evaluation of hearing by studying acoustic distortion products in noise-induced hearing loss].

In this work, the Authors want to verify the possibility of an objective method of cochlear function evaluation in subjects affected by chronic acoustic trauma, through the study of the acoustic distortion products. Undertaking 46 subjects, the researchers have demonstrated a direct correlation between the tonal acoustic threshold and that of the distortion products. This method was able to show the useful indications of an objective evaluation of acoustic capacity in non collaborating subject. Because of the large variability of intensity of the distortion products and their absence when the acoustic threshold is more than 50-60 dB HL, they by themselves, don't permit exact evaluation of the tonal threshold for a given frequency.