Dorsomedial Prefrontal Cortex Repetitive Transcranial Magnetic Stimulation for Tinnitus: Promising Results of a Blinded, Randomized, Sham-Controlled Study.

OBJECTIVES: Tinnitus is the perception of sound in ears or head without corresponding external stimulus. Despite the great amount of literature concerning tinnitus treatment, there are still no evidence-based established treatments for curing or for effectively reducing tinnitus intensity. Sham-controlled studies revealed beneficial effects using repetitive transcranial magnetic stimulation (rTMS). Still, results show moderate, temporary improvement and high individual variability. Subcallosal area (ventral and dorsomedial prefrontal and anterior cingulate cortices) has been implicated in tinnitus pathophysiology. Our objective is to evaluate the use of bilateral, high frequency, dorsomedial prefrontal cortex (DMPFC) rTMS in treatment of chronic subjective tinnitus. DESIGN: Randomized placebo-controlled, single-blinded clinical trial. Twenty sessions of bilateral, 10 Hz rTMS at 120% of resting motor threshold of extensor hallucis longus were applied over the DMPFC. Fourteen patients underwent sham rTMS and 15 were submitted to active stimulation. Tinnitus Handicap Inventory (THI), visual analog scale, and tinnitus loudness matching were obtained at baseline and on follow-up visits. The impact of intervention on outcome measures was evaluated using mixed-effects restricted maximum likelihood regression model for longitudinal data. RESULTS: A difference of 11.53 points in the THI score was found, favoring the intervention group (p = 0.05). The difference for tinnitus loudness matching was of 4.46 dB also favoring the intervention group (p = 0.09). CONCLUSIONS: Tinnitus treatment with high frequency, bilateral, DMPFC rTMS was effective in reducing tinnitus severity measured by THI and matched tinnitus loudness when compared to sham stimulation.

Bilateral Dorsomedial Prefrontal Cortex rTMS for Tinnitus Treatment: A Successful Case.

We present a successful tinnitus treatment case with intensity and distress reduction in a patient subjected to bilateral 10 Hz repetitive transcranial magnetic stimulation (rTMS) to the dorsomedial prefrontal cortex (DMPFC). Subjective tinnitus is the perception of sound in the ears or head when no corresponding external stimulus exists. Approximately 1%-2% of the population report severe tinnitus with daily life impairment. Sham-controlled studies have revealed benefits using rTMS in tinnitus, although the improvement is moderate or temporary, indicating the need for new strategies. Evidence that the DMPFC is important in tinnitus pathophysiology makes this area a promising target. A 51-year-old male patient with a 4-year history of treatment-resistant moderate bilateral tinnitus was treated with 20 sessions of bilateral 10 Hz DMPFC rTMS. The patient showed important reduction and sustained 4-month response in tinnitus loudness and annoyance, 24 point drop in tinnitus handicap inventory, visual analog scale reduction to zero, and tinnitus loudness of 1 dB compared to baseline 15 dB. Tinnitus treatment is challenging and new alternatives are needed. To our knowledge, this is the first report using rTMS to the DMPFC for tinnitus. In this protocol, important and sustained reduction of tinnitus annoyance and loudness was obtained. This outcome of the case suggests that this approach is promising for treating tinnitus and is worth further investigation.