Master Thesis
Invasive neuromodulation as a possible treatment for tinnitus
Background:
Tinnitus is the perception of a meaningless sound which does not originate from an external sound source. It affects a large part of our population and can have a serious impact on people's lives. Many different therapies have been suggested, but few are evidence based and none has proven to be effective for all tinnitus sufferers so far. Neuromodulation techniques for tinnitus are currently under investigation. Non-invasive neuromodulation is already implemented quite often, although a Cochrane systematic review from 2011 concludes that there is very limited support to recommend this treatment. The fact that some patients did respond well to non-invasive neuromodulation, opened the door to try more invasive techniques. As new and more detailed hypotheses for the pathophysiology of tinnitus arise, more central types of invasive neuromodulation gain interest.
Objectives:
We aimed to collect and review the published studies on invasive neuromodulation techniques for the therapy of tinnitus and to assess whether these results seem promising for the future. The included techniques are deep brain stimulation, cortical stimulation, vestibulocochlear nerve and vagus nerve stimulation.
Search methods:
MEDLINE and Embase databases were scanned for articles using PRISMA guidelines.
Results and conclusion:
In total, 22 studies were included in this systematic review. There are 2 randomized controlled trials who found no effect of cortical stimulation during the blinded phase. Other cortical stimulation trials show more promising results, especially for unilateral, pure tone tinnitus. However, the evidence is of low quality. Deep brain stimulation studies are mostly pilot studies where some patients responded with a decrease in tinnitus loudness or severity, but there are no placebo results to compare. Invasive stimulation of the vagus nerve shows a general decrease in tinnitus severity and an improved depression score but there is no decrease in tinnitus loudness and again, these studies are not placebo controlled. Cochlear nerve stimulation transformed the tinnitus percept in a more pleasant sound in two trials, but there was no change in loudness. Due to the limited quality of literature at this moment, it is not possible to draw conclusions about the effectiveness of invasive neuromodulation techniques for the treatment of tinnitus. At this moment risk/benefit ratio is not favourable for such an invasive technique and should not be recommended in general, although some promising effects are mentioned. Further research must be encouraged to gain more insight in this matter.
Celine Marechal
Submitted in 2018
Master of Medicine in Medicine
University of Gent
Invasive neuromodulation as a possible treatment for tinnitus
Background:
Tinnitus is the perception of a meaningless sound which does not originate from an external sound source. It affects a large part of our population and can have a serious impact on people's lives. Many different therapies have been suggested, but few are evidence based and none has proven to be effective for all tinnitus sufferers so far. Neuromodulation techniques for tinnitus are currently under investigation. Non-invasive neuromodulation is already implemented quite often, although a Cochrane systematic review from 2011 concludes that there is very limited support to recommend this treatment. The fact that some patients did respond well to non-invasive neuromodulation, opened the door to try more invasive techniques. As new and more detailed hypotheses for the pathophysiology of tinnitus arise, more central types of invasive neuromodulation gain interest.
Objectives:
We aimed to collect and review the published studies on invasive neuromodulation techniques for the therapy of tinnitus and to assess whether these results seem promising for the future. The included techniques are deep brain stimulation, cortical stimulation, vestibulocochlear nerve and vagus nerve stimulation.
Search methods:
MEDLINE and Embase databases were scanned for articles using PRISMA guidelines.
Results and conclusion:
In total, 22 studies were included in this systematic review. There are 2 randomized controlled trials who found no effect of cortical stimulation during the blinded phase. Other cortical stimulation trials show more promising results, especially for unilateral, pure tone tinnitus. However, the evidence is of low quality. Deep brain stimulation studies are mostly pilot studies where some patients responded with a decrease in tinnitus loudness or severity, but there are no placebo results to compare. Invasive stimulation of the vagus nerve shows a general decrease in tinnitus severity and an improved depression score but there is no decrease in tinnitus loudness and again, these studies are not placebo controlled. Cochlear nerve stimulation transformed the tinnitus percept in a more pleasant sound in two trials, but there was no change in loudness. Due to the limited quality of literature at this moment, it is not possible to draw conclusions about the effectiveness of invasive neuromodulation techniques for the treatment of tinnitus. At this moment risk/benefit ratio is not favourable for such an invasive technique and should not be recommended in general, although some promising effects are mentioned. Further research must be encouraged to gain more insight in this matter.
Celine Marechal
Submitted in 2018
Master of Medicine in Medicine
University of Gent
