Objective: Clinical, neurophysiological and neuroimaging data suggest that chronic tinnitus resembles neuropsychiatric syndromes characterised by focal brain activation. Low frequency repetitive transcranial magnetic stimulation (rTMS) has been proposed as an efficient method in treating brain hyperexcitability disorders.
Methods: Patients suffering from chronic tinnitus underwent a [ (18)F]deoxyglucose-PET (positron emission tomography). Fusioning of the individual PET scan with the structural MRI-scan (magnetic resonance imaging, T1, MPRAGE) revealed an increased metabolic activation in the primary auditory cortex as target point for rTMS. A neuronavigational system enabled the positioning of the figure of eight coil in relation to the target area. rTMS (110 % motor threshold; 1 Hz; 2000 stimuli/day over 5 days) was performed using a placebo controlled cross-over design.
Results: Following active rTMS there was a moderate improvement of tinnitus perception. Treatment effects lasted up to six months in some patients.
Conclusions: Neuronavigated rTMS offers new possibilities in the understanding and treatment of chronic tinnitus.