Long-term effects of repetitive transcranial magnetic stimulation in unilateral tinnitus

Abstract

OBJECTIVES/HYPOTHESIS: We investigated the long-term effects of repetitive transcranial magnetic stimulation (rTMS) delivered to the temporoparietal junction and compared contralateral and ipsilateral application in patients with unilateral tinnitus. STUDY DESIGN: Prospective study. METHODS: A total of 61 patients with asymmetric hearing loss and nonpulsatile chronic tinnitus localized to the poorer ear who were refractory to medical treatment were enrolled. Patients were randomly assigned to one of two treatment groups: 1-Hz stimulation applied to the temporoparietal junction either ipsilaterally (n = 30) or contralaterally (n = 31) to the symptomatic ear. Changes in the Tinnitus Handicap Inventory (THI) scores and self-rating visual analog scores (VAS) for loudness, awareness, and annoyance were analyzed before and after treatment for 6 months. Improved patients were defined as those with decreases in their THI scores by >10 points and 20%. RESULTS: There were no major complications or worsening of hearing. When analyzing the THI scores and VAS pre-rTMS and 6 months after rTMS, significant decreases were observed in patients overall (P < .001). For the comparison of long-term outcomes between the ipsilateral and contralateral stimulation groups, there were no differences in the degree of decrease in THI scores or VAS (P > .05). In addition, there was no significant difference in the rate of patients who improved between the ipsilateral (14 of 30) and contralateral (16 of 31) stimulation groups (P = .800). The ipsilateral group showed a more rapid improvement than the contralateral group. CONCLUSIONS: Daily application of 1-Hz rTMS to the temporoparietal area is safe and has long-term beneficial effects. The laterality of stimulation is not the decisive factor.