Neuropediatrics 2005; 36 - V12
DOI: 10.1055/s-2005-867971

Direct EEG changes during Vagus Nerve Stimulation comparing on and off time in children with pharmacoresistant epilepsy

J Sperner 1, H Fiebelkorn 2, J Mertin 1, HJ Friedrich 3
  • 1Klinik für Kinder- und Jugendmedizin, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Neuropädiatrie, Lübeck
  • 2Technische Fachhochschule Lübeck, Fachbereich Elektrotechnik, Lübeck
  • 3Universitätsklinikum Schleswig-Holstein, Zentrale Universitätsverwaltung, Lübeck

Objectives: To evaluate quantitative changes of EEG background activity from VNS stimulation on and off time period.

Material and Methods: : 65 EEGs of 15 children chronically treated with VNS were examined using Fourier analysis. Summarising at least 60s VNS on time periods were compared with off time periods of the same EEG. Changes of spectral power and frequency bands were determined for 17 electrodes of the 10–20 system, significant differences were calculated using SSPS (Mann-Whitney U, Kruskal-Wallis, Wilcoxon) in different groups.

Results: Significant differences were found comparing on and off time periods of all EEGs, more pronounced on the left hemisphere. Frequency bands showed more prominent changes than power spectra. Higher stimulation output current caused a decrease of alpha band and increase of the delta band. The stimulation frequency artefact of 30Hz was observed more frequently in responders than in nonresponders, VNS responders showed only left sided changes with decrease of alpha band and increase of fast Beta3 band.

Conclusions: This study showed for the first time, that EEG background activity is changed during on and off time of VNS. It is supposed, that these changes might be helpful to explain the mechanism of action in this new nonpharmacological antiepileptic treatment.