The relationship between tinnitus pitch and parameters of audiometry and distortion product otoacoustic emissions

Objectives: Chronic tinnitus is associated with reduced auditory input, which results in changes in the central auditory system. This study aimed to examine the relationship between tinnitus pitch and parameters of audiometry and distortion product otoacoustic emissions. For audiometry, the parameters represented the edge frequency of hearing loss, the frequency of maximum hearing loss and the frequency range of hearing loss. For distortion product otoacoustic emissions, the parameters were the frequency of lowest distortion product otoacoustic emission amplitudes and the frequency range of reduced distortion product otoacoustic emissions. Method: Sixty-seven patients (45 males, 22 females) with subjective chronic tinnitus, aged 18 to 73 years, were included. Results: No correlation was found between tinnitus pitch and parameters of audiometry and distortion product otoacoustic emissions. However, tinnitus pitch fell mostly within the frequency range of hearing loss. Conclusion: The current study seems to confirm the relationship between tinnitus pitch and the frequency range of hearing loss, thus supporting the homeostatic plasticity model.