耳鳴の臨床統計的検討

抄録

Cases of tinnitus totaling up to 163 examined at the Oto-Rhino-Laryngological Clinic of Tottori University Hospital have been reviewed. They consisted of 78 men and 85 women aged from 15 to 84 years. Tinnitus was attempted to be expressed verbally by onomatopoeia. The most frequent expression was “geen” [d i n]. Pitch matching and loudness matching tests were carried out in 146 patients. The most frequently observed pitch and loudness of tinnitus was 8000Hz and 0dB HL., respectively. The masking curve examined by bands of noise showed 7 types, including the convergence type (42% of 77 cases). Residual inhibition (RI) was studied by 1-min delivery of bands of noise in 82 cases, in 58 of which RI was positive. Effects of i. v. injected lidocaine (60mg for males, 40mg for females) were examined in 121 cases: tinnitus disappeared entirely in 39 cases; and was reduced partially in 53. The i. v. injected agent was effective in most of the RI-positive cases. To sum up these findings and ones obtained by auditory brain-stem response examination, suppression of tinnitus by RI and i. v. injected lidocaine may result from participation in the brain stem.