Over Neuromodulatie

  • De grootste groep patienten met Tinnitus is die waarvan de oorzaak gezocht moet worden in het gehoorverlies. De hersenen “vullen”  als het ware de verloren gegane frequenties aan en creeëren zo een “fantoom-geluid” . Het is dan niet verwonderlijk dat er ook gezocht wordt naar mogelijkheden om de hersenen te vertellen dat niet meer te doen. Éen van de methodes is precies dat geluid toe te voegen dat de patient normaliter hoort en zo de hersenen via de oren te bedotten. Het probleem is echter om precies die frequentie te vinden die de tinnitus veroorzaakt. Dit is beschreven op de pagina “Audiogram on line”. 
    Een andere methode is direct in het brein aan te spreken met de enige vorm die het kent: elektromagnetische energie. 
  • rTMS rTMS: repetitive Transcranial Magnetic Stimulation in which certain parts of the brain are stimulated by placing electromagnets on the skull.
  • TDCS: Transcranial Direct Current Stimulation
  • NVS: Nervus Vagus Stimulation

rTMS

Transcranial magnetic stimulation (rTMS) is a non-invasive form of neuromodulation in which an electromagnet is placed on the skull that generates magnetic fields with short pulses. The magnetic field produces electric currents that activate superficial cortical neurons. The aim of this technique is to modulate the activity of brain cells, thereby inhibiting overactive areas that cause tinnitus. There is little risk of side effects when using repetitive transcranial magnetic stimulation (rTMS) in the treatment of patients with tinnitus, but on the other hand, the published results are highly variable. Based on the literature and other information found, there is still insufficient evidence for the effectiveness of rTMS as a therapy for tinnitus
The position of the Dutch Society for Throat Nose and Ear Surgery, as described in the “richtlijn tinnitus”  is therefore not to offer rTMS as a treatment for tinnitus.
A variant of this rTMS is that in which extradural electrodes are implanted under the skull and provide electrical stimulation across the auditory cortex. The cable-connected electro stimulator is placed in the abdominal wall of the patient. There are (experimental) indications that rTMS has an effect on tinnitus, but more research is needed to determine this.

TDCS

tDCS is a neuromodulative, non-invasive and painless technique in which the left temporoparietal region of the brain is stimulated by a weak electrical current. Publications have reported that patients who have undergone tDCS have reported no side effects (such as headache, neck pain, and worsening of tinnitus). There appears to be a positive effect of tDCS on the severity of tinnitus, but the results are based on (too) small groups of patients and too few studies to confirm the results. The position of the Dutch Association for Ear, Nose and Throat Surgery, is described in the “Guideline Tinnitus” is therefore not to offer rDCS as a treatment for tinnitus for the time being. “richtlijn tinnitus”  is dan ook om rDCS vooralsnog niet aan te bieden als behandeling van tinnitus

NVS

The nervus vagus is the tenth cranial nerve. It belongs to the twelve cranial or cranial nerves, which arise directly from the brain and not from the spinal cord. The nerve contains descending and ascending pathways, consisting of motor fibers, sensory fibers, taste fibers, and fibers belonging to the involuntary nervous system. The vagus nerve supplies parts of the head – like the other cranial nerves – but also runs to the thoracic and abdominal cavities, where it branches into the viscera. A misaligned cerebral cortex is one of the possible explanations for the Tinnitus phenomenon so neuromodulating by stimulating one of the main nerve supplying nerves to the auditory center in the brain may provide relief. The first experiments do indeed point in that direction. A description of these first experiments can be found here 
The fact that the nervus vagus is such a complex nerve with ascending and descending fibers with many different functions immediately indicates the problem: how exactly can you stimulate those fibers that lead to the desired area, without stimulating fibers that supply other organs? or in the case of ascending fibers stimulate or influence other parts of the brain.
Toch zijn er mensen die al zulke zenuwstimulatie ontvangen. Weliswaar voor een andere indicatie ( epilepsie , depressie en migrainepatiënten) maar het basisprincipe is identiek, maar veel onderzoek is nog nodig,