La terapia degli acufeni mediante elettrostimolazione transcutanea

It has been shown that the electric stimulation of the round window, performed during the study of possible candidates for a cochlear implant, can temporarily inhibit tinnitus. On the basis of these results a new form of therapy for tinnitus based on the electric stimulation of the auricular cutaneous region, was proposed. The authors have applied this therapy to 80 cases of severe tinnitus, resistant to other treatments. Two different types of current were utilized: 1) 85 Hz biphasic spike waves in a continuous current; 2) 85 Hz biphasic spike waves trains of a frequency of 3 Hz. The cathode was applied before the tragus and the anode on the mastoid. Favourable clinical results measured on the basis of the patients subjective evaluation were attained in 40% of the considered cases. A correlation between these results and age, sex, audiometric characteristics, localization, pitch and duration of tinnitus was looked for; unilaterality of tinnitus and normo-acusis resulted to be favourable prognostic factors but no statistically significative correlations were evidenced. The authors think that electric transcutaneous stimulation might inhibit tinnitus through a double mechanism: a peripheral one directly on the cochlea, and a central one through a possible activation of Resmussen olivo-cochlear bundle, mediated by the stimulation of peripheral sensorial branches of the V, VII and X cranial nerves.