[Study on treatment of chronic tinnitus by tetanus stimulation and evaluation methods of tinnitus].

Objective: The purpose of this study was to explore the efficacy of tetanus stimulation in tinnitus treatment and the correlation between the mainstream questionnaires of tinnitus and tinnitus-matching in order to find a more convenient and accurate method for tinnitus evaluation. Method: Ten patients with chronic tinnitus and normal or mild hearing impairment were enrolled in this study, totaling 13 ears. Their age ranged from 23 to 53 years old. The stimulus sound（white noise, frequency modulation 14.1 Hz, repetitive amplitude modulation, duty cycle 0.5） was selected and the sound intensity was 50 dB SL. Experimental procedure: （4 minutes sound stimulation+4 minutes rest） ×4 times, totaling 32 minutes. The patients were treated three times a week for 5 weeks. The loudness of tinnitus was matched before and after each treatment, and tinnitus handicap inventory（THI）, tinnitus handicap questionnaire（THQ） and visual analog scales（VAS） were also used for assessment before the first treatment each week. The loudness matching and the above scales were performed once more at follow-up for one week after end-of-treatment. Result: ①Single treatment: the matched loudness value decreased by 1.000（0.000, 3.000） dB（ Z =7.553, P <0.01） after each single treatment. ②After five weeks' treatment: the matched loudness value decreased（9.692±8.038） dB（ t =4.348, P <0.01）; VAS value decreased by 2.000（1.000, 3.000）（ Z =2.890, P <0.01）; total score of THQ decreased（7.389%±8.847%）（ t =2.641, P <0.05）. ③Correlation analysis: there was positive correlation between total scores of THI and THQ（ r =0.747, P <0.01）; the matched loudness values have positive correlation with VAS value（ r =0.593, P <0.01）, THI-F（ r =0.346, P <0.01） and THQ-factor 3 score（ r =0.294, P <0.05）; there was positive correlation between the VAS value and THI-F（ r =0.326, P <0.05）, the total score of THI（ r =0.466, P <0.01）, THQ-factor 3 score（ r =0.291, P <0.05）, the total score of THQ（ r =0.497, P <0.01）. Conclusion: The loudness of tinnitus declined with significant fluctuation during tetanus sound therapy. THQ scale is recommended as a sensitive indicator for evaluating the efficacy of tinnitus treatment; VAS is recommended for rapid assessment of tinnitus. Tetanus stimulation is expected to become an important direction in tinnitus sound therapy.