The Effect of Electrical Stimulation at Tympanic Membrane on Tinnitus Suppression / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Electrical stimulation is one of various methods of treatment for patients suffering from tinnitus. However, the effect or mechanism of electrical stimulation is still unclear. Also, although the success rate of electrical stimulation ranged from 13% to 80% in other studies, the best condition of electrical stimulation is unknown yet. The purpose of this study is to elucidate the effect of alternate current electrical stimulation at tympanic membrane on tinnitus suppression and to seek the best condition that yield maximum tinnitus reduction. SUBJECTS AND METHOD: Forty-five patients who suffered from tinnitus with moderately severe hearing loss above 56 dB and 20 patients with limited frequency hearing loss above 56 dB were selected for this study. The study was performed in 4 phases. Fourty-five patients who passed the screening phase received 10 min duration of electrical stimulation twice a week for 6 weeks. RESULTS: The results were as follows. 1) Among the 65 patients, alternate current stimulation suppressed tinnitus in 45 patients (69%) in the screening phase. So 45 patients were selected for the electrical stimulation group. 2) Tinnitus suppression was most effective in patients with sudden deafness in the screening phase. 3) Effective tinnitogram for electrical stimulation was white noise and 8 kHz (pure tone) in the screening phase. 4) The most common optimal stimulation was the low frequency square wave. 5) The mean intensity of the current was 47.5 microliterA. 6) Suppression of tinnitus was achieved in 30 patients (67%) among 45 patients who received electrical stimulation therapy. 7) Long term treatment was more effective than short term, but adaptation phenomenon was noted during the treatment phase in 15 patients (33%). CONCLUSION: These results showed that alternate current stimulation for patients with tinnitus is effective and that the optimal condition to use is the low frequency square wave. We found good response to electrical stimulation in patients with sudden deafness and moderate to severe hearing loss. Therefore, we think electrical stimulation is a good treatment for patients with tinnitus for whom it is difficult to apply TRT (tinnitus retraining therapy).