[Effects of electrical promontory stimulation and band-noise masker in the suppression of tinnitus].

The effects of electrical promontory stimulation (EPS) and band-noise masker (BNM) were examined in 102 patients suffering from tinnitus. The effects of EPS were as follows: complete suppression in 8 patients (8%), partial suppression in 53 patients (52%), no effect in 40 patients (39%), and exacerbation in 1 patient (1%). The effects of BNM were also studied in the same population of patients and the results were as follows: complete suppression in 8 patients (8%), partial suppression in 39 patients (38%) and no effect in 55 patients (54%). The change in the loudness of tinnitus was objectively evaluated, using the loudness-balance test (LBT), after EPS or BNM. The results of LBT correlated with the subjective complaints of tinnitus. In contrast, the pitch match test (PMT) failed to show any remarkable change after EPS or BNM. EPS was more effective in patients with sudden deafness than in those with presbycusis. On the other hand, BNM was more effective in the patients with presbycusis. The mechanisms of suppression of tinnitus by EPS and BNM are discussed.