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).
Subject(s)
Humans , Electric Stimulation Therapy , Electric Stimulation , Hearing Loss , Hearing Loss, Sudden , Mass Screening , Noise , Tinnitus , Tympanic MembraneABSTRACT
BACKGROUND AND OBJECTIVES: The Nucleolar organizer regions (NORs) are one of markers of cellular proliferation. Because the NORs can be visualized by a silver staining technique, the NORs are called the argyrophilic nucleolar organizer regions (AgNORs). The expression patterns of proliferative markers have been reported in the cholesteatoma, but the AgNORs have not been studied in the cholesteatoma. We investigated the proliferative activities of the cholesteatoma by the AgNORs and the usefulness of the AgNORs as a proliferative index in the cholesteatoma. MATERIALS AND METHODS: We assessed 5 postauricular skin samples and 20 cholesteatoma specimens by the numbers of the total AgNORs and the large AgNORs (large AgNOR means a diameter of over 6 nm) in high power fields and each cell. And the total areas of the AgNORs in high power fields (HPF) were calculated. RESULTS: The numbers of the large AgNORs in HPF, the numbers of AgNORs in each cell and the total areas of the AgNORs in HPF of the cholesteatoma were higher than those of the controls (p<0.05). In the cholesteatoma, the numbers of the large AgNORs and the total areas of the AgNORs in HPF were the highest in the keratinizing squamous epithelium of thick portion followed by the non-keratinizing squamous epithelium, and the keratinizing epithelium of thin portion. The numbers of the large AgNORs in each cell of the basal and superficial layers were the highest in the thick keratinizing squamous epithelium. In the suprabasal layer, the non-keratinizing squamous epithelium showed higher numbers of the large AgNORs but showed no statistical significance. CONCLUSION: 1) The proliferative capacity of the epithelium of cholesteatoma is reactive proliferative status. 2) The proliferative activity is varied with the differentiation status of the squamous epithelium in the cholesteatoma.