Objectives: This study aims to assess ears with tinnitus and without distortion product otoacoustic emissions (DPOAE) in patients with and without hearing loss and to classify the tinnitus symptoms on the basis of tinnitus severity index (TSI) and tinnitus handicap inventory (THI) in both groups.
Patients and methods: A total of 102 patients with tinnitus symptoms were included in the study. Of these patients, 48 had (32 males, 16 females; mean age 45±8.9 years) normal hearing and 54 patients (42 males, 12 females; mean age 52±12.1 years) had hearing loss. Pure tone audiogram, high-frequency audiometer and DPOAE were applied to patients. Tinnitus symptoms of patients were assessed with TSI and THI.
Results: Significantly higher tinnitus severity was monitored in group with hearing loss compared with group with normal hearing (p=0.024). There was a significant similarity in the frequencies affected from tinnitus between the groups (p<0.001). The TSI and THI showed significant similar results between two groups (p<0.001). A significant decrease was found in ears with tinnitus in frequencies of 1000 Hz, 2000 Hz, 3000 Hz, 4000 Hz and 6000 Hz with DPOAE compared to the ears without tinnitus in group with normal hearing (p<0.05).
Conclusion: Our study results show that patients with TSI and THI are affected by tinnitus at the same rate in daily life whether they have hearing loss or not, but those with hearing loss have a higher tinnitus severity. Decreased DPOAE responses can be found in patients with normal hearing, which can be more profound in low-frequency tinnitus, particularly.