Tinnitus Is Associated With Extended High-frequency Hearing Loss and Hidden High-frequency Damage in Young Patients

To analyze the results of extended high-frequency (EHF) and high-frequency hearing tests in young patients with tinnitus who show normal response in conventional pure-tone audiometry (PTA), and to explore the correlation between tinnitus and hearing loss (HL). STUDY DESIGN: A case–control study. SETTING: A Tertiary Eye Ear Nose & Throat Hospital of China. PARTICIPANTS: Patients with tinnitus, aged 18 to 35 years old, and with normal conventional PTA (125 Hz–8 kHz) were enrolled in the tinnitus group. Volunteers without tinnitus of the same age were enrolled in the control group. MAIN OUTCOME MEASURES: The incidence of EHF-HL and the hearing thresholds at each frequency, as well as the distribution of maximum HL frequency and edge frequency in all participants were compared. RESULTS: In total, 28 cases (43 ears) were enrolled in the tinnitus group and 34 cases (68 ears) in the control group. The incidence of EHF-HL, average hearing threshold of each frequency ranging from 4 to 16 kHz, and the maximum hearing threshold were significantly higher in the tinnitus group. The edge frequency in the tinnitus group was lower than that in the control group (10.4 ± 3.1 kHz versus 12.3 ± 2.5 kHz, p = 0.010). The dominant tinnitus pitch in cases whose EHF was impaired was positively correlated with the hearing-level loudness of tinnitus (r = 0.627, p < 0.001). CONCLUSION: Patients with tinnitus and normal hearing in conventional PTA showed signs of EHF-HL and hidden damage in the high-frequencies more easily. EHF hearing tests and the follow-up of HF hearing tests are recommended to facilitate early detection of hearing impairment for timely intervention.