Therapeutic applications of rTMS for tinnitus

Abstract

Tinnitus, the phantom perception of sound in the absence of a corresponding acoustic signal, is a frequent disorder which is difficult to treat. Cognitive behavioral therapy can effectively facilitate the habitation to the phantom sound, but there exist no established therapeutic options for reducing the intensity or the loudness of tinnitus. Thus, there is an urgent need for more effective treatment approaches. Functional imaging studies in tinnitus patients have revealed alterations in both auditory and nonauditory brain areas, which represent potential targets for treatment via repetitive transcranial magnetic stimulation (rTMS). Single sessions of rTMS over the temporal or temporoparietal cortex have been successful in transiently reducing tinnitus perception. Many but not all randomized controlled trials have revealed that repeated sessions of rTMS result in a significant reduction of tinnitus severity. However, available studies vary in methodological quality, variability in treatment results is high both within and across studies, effect sizes of rTMS in the reduction of tinnitus severity are only moderate, and only few studies assessed long-term outcome. Thus, even if quality of evidence is high, currently only a weak recommendation can be given for the use of rTMS for the treatment of chronic tinnitus.