Transcutaneous vagus nerve stimulation
see Transcutaneous Vagus Nerve Stimulation for Severe Traumatic Brain Injury
The transcutaneous vagus nerve stimulation (tVNS) is a non-invasive technique in the treatment of drug-resistant epilepsy and results in positive effects for patients who cannot tolerate invasive vagus nerve stimulation. In a study, Wu et al. aimed to define the relationship between tVNS and seizure control, quality of life (QOL) and some other factors.
They found articles by searching through PubMed and Web of Science, and a total of three articles with 280 patients overall were included. These eligible studies include two randomized double-blinded trials and one randomized single-blinded trial. Meta-analysis and systematic review were performed, analyzing the association between tVNS and seizure frequency using the available data. The responder rate, QOL and adverse effects were also analyzed.
The results showed a significant difference in seizure frequency between treatment group and control group (Z = 2.14, P = 0.03, 95% confidence interval (CI) -6.31 to -0.27; I2 = 10%). However, only two studies provided the data of responders, and the result failed to figure out a significant difference (Z = 0.75, P = 0.45, 95% CI (odds ratio) 1.47 (0.54-4.02); I2 = 61%). It is difficult to define whether tVNS improved QOL between treatment and control groups using the available data. The adverse effects seem to be very few, with the most common being a headache.
tVNS is an effective procedure to control the frequency of seizures according to the available data, especially for those patients who do not want to tolerate a surgical procedure 1).
Bauer S, Baier H, Baumgartner C, Bohlmann K, Fauser S, Graf W, Hillenbrand B, Hirsch M, Last C, Lerche H, Mayer T, Schulze-Bonhage A, Steinhoff BJ, Weber Y, Hartlep A, Rosenow F, Hamer HM. Transcutaneous Vagus Nerve Stimulation (tVNS) for Treatment of Drug-Resistant Epilepsy: A Randomized, Double-Blind Clinical Trial (cMPsE02). Brain Stimul. 2016 May-Jun;9(3):356-363. doi: 10.1016/j.brs.2015.11.003. Epub 2016 Jan 20. PubMed PMID: 27033012.