Deep Brain Stimulation for Refractory Tinnitus

Tinnitus is the perception of a sound in the absence of an audible source. Currently up to 15% of the general population suffers chronically from tinnitus. The most severe degree of tinnitus ís experienced by 2.4% of the population and is associated with insomnia, depression; anxiety and even suicide. Up to date there is no effective standard therapy. Current therapies mostly focus on treating the distress caused by tinnitus instead of reducing the actual phantom sound. Nevertheless, many patients do not benefit from the current approaches and become severe and chronic tinnitus sufferers. In these patients neuromodulation-based treatments can be a promising option. Tinnitus perception is associated with many complex changes in several different brain structures. The general accepted hypothesis is that neuronal changes occur in both auditory and non-auditory brain structures, most often as a compensating mechanism on reduced input from the auditory nerve caused by cochlear hair cell damage. These central neuronal changes include an increase in spontaneous firing rate, synchronized activity, bursting activity and tonotopic reorganization. In high-frequency deep brain stimulation (DBS) a reversible lesion-like effect is mimicked. From findings in Parkinson's disease patients who also had tinnitus and were treated with DBS, it is known that stimulation can alter or even completely diminish perception of tinnitus. It can be expected that modulation of specific structures within the complex tinnitus pathways can disrupt pathological neuronal activity and thereby alter tinnitus perception or distress caused by this phantom sensation. The investigators found in animal studies that DBS in the central auditory pathway can indeed significantly decrease tinnitus-like behavior. In a questionnaire study the investigators found that around one-fifth of the patients would be reasonably willing to accept invasive treatments and one-fifth would be fully willing to undergo invasive treatment like DBS. Based on preclinical studies and human case studies, the investigators expect that DBS of the central auditory pathway will inhibit tinnitus perception and distress caused by this phantom sensation. Based on studies performed within Maastricht University Medical Center (MUMC), the investigators selected the medial geniculate body of the thalamus (MGB) as the most potential target to treat tinnitus with DBS.