Invasive und transkutane Vagusnervstimulation: Ein Vergleich beider Stimulationsarten hinsichtlich Effizienz sowie lebensqualitativer Aspekte bei therapierefraktärer Epilepsie - Untersuchungen durch das Epilepsiezentrum Marburg

Approximately 50 million people worldwide suffer from epilepsy. Despite anticonvulsive therapy, one third still experience seizures. For such patients, invasive (iVNS) or transcutaneous (tVNS) vagus nerve stimulation presents a therapeutic option. The aim of our study was to analyze, evaluate and compare the long-term outcome of both treatment options. Within the framework of a retrospective study that included 34 patients with an invasive vagus nerve stimulator and ten with a transcutaneous vagus nerve stimulator, all of whom were treated at the Marburg Epilepsy Center (Epilepsiezentrum Marburg), the necessary information was collected using medical reports, questionnaires and interviews. iVNS and tVNS patients were treated for a mean of 60 and 48 months, respectively. The maximum follow-up was ten years for individuals with iVNS and five years for those with tVNS. Thirty percent of those treated with vagus nerve stimulation reported a seizure frequency reduction of at least 50%. Another 20% of the patients with iVNS and 10% of the patients with tVNS were observed to be completely free of seizures. Invasive vagus nerve stimulation was associated with a higher rate of adverse events in comparison to those with transcutaneous vagus nerve stimulation (84,85% vs. 41,67%). The most frequent adverse effect of invasive stimulation was hoarseness. In comparison to invasive stimulation, the patients with transcutaneous stimulators suffered only local side effects resulting from the device. With an average of one side effect per person both treatment options can be perceived as well-tolerated. Under therapy with iVNS our study recorded improvements in mood and concentration. Those with tVNS also reported these effects, although to a lesser degree. Both devices resulted in a significant improvement in the quality of life by 20%. We concluded that both stimulators are a safe, tolerable and effective treatment option for therapy-resistant epilepsy in adults. For those candidates suitable for either the invasive or transcutaneous devices, we would suggest choosing the transcutaneous option. It offers a comparable efficacy and avoids the risk of significant surgical complications. Furthermore, it is more cost-efficient than invasive stimulation. If the impact is positive, the use of an invasive stimulator remains an option. Subsequent research opportunities are for example the implementation of comparatistics and the clarification of the detailed functioning of the vagus nerve stimulation.