title: A retrospective analysis of the effects of magnet-activated stimulation in conjunction with vagus nerve stimulation therapy.
abstract: Vagus nerve stimulation (VNS) therapy offers two methods to help control seizures, automatic stimulation delivered at programmed intervals and on-demand stimulation initiated with a magnet. This study retrospectively analyzes magnet use during the E03 and E04 clinical trials of VNS therapy. Magnet activation that aborted, decreased, terminated, or diminished a seizure was classified as an improvement; for purposes of evaluation, the patient was considered to have received a benefit. When patients in the E03 trial used magnets to activate stimulation, patients with active magnets were more likely to report seizure improvement than patients with inactive magnets (P=0.0479, Fisher's test). In the E04 trial, 22% of patients using the magnet reported seizure termination and 31% reported seizure diminution. Unrelated to seizure reduction with programmed VNS therapy, approximately half of the patients who used the magnet in this study received some benefit. Additional studies can provide a better understanding of this unique mode of delivering antiseizure therapy.
authors.affiliation: Regional Epilepsy Center, 2801 West Kinnickinnic River Parkway, Suite 570, 53215, Milwaukee, WI, USA.
authors.forename: George L
authors.initials: GL
authors.lastname: Morris
mesh_terms: D000927:Anticonvulsants / Q000627:therapeutic use; D004307:Dose-Response Relationship, Radiation; D004311:Double-Blind Method; D004558:Electric Stimulation / Q000379:methods*; D004599:Electric Stimulation Therapy / Q000379:methods*; D006801:Humans; D008137:Longitudinal Studies; D008280:Magnetics; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D012640:Seizures / Q000628:therapy*; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D013997:Time Factors; D016896:Treatment Outcome; D014630:Vagus Nerve / Q000503:physiopathology / Q000528:radiation effects*
chemical_list: D000927:Anticonvulsants