AUTHOR=Suresh Hrishikesh , Mithani Karim , Brar Karanbir , Yan Han , Strantzas Samuel , Vandenberk Mike , Sharma Roy , Yau Ivanna , Go Christina , Pang Elizabeth , Kerr Elizabeth , Ochi Ayako , Otsubo Hiroshi , Jain Puneet , Donner Elizabeth , Snead O. Carter , Ibrahim George M. TITLE=Brainstem Associated Somatosensory Evoked Potentials and Response to Vagus Nerve Stimulation: An Investigation of the Vagus Afferent Network JOURNAL=Frontiers in Neurology VOLUME=12 YEAR=2022 URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2021.768539 DOI=10.3389/fneur.2021.768539 ISSN=1664-2295 ABSTRACT=

Despite decades of clinical usage, selection of patients with drug resistant epilepsy who are most likely to benefit from vagus nerve stimulation (VNS) remains a challenge. The mechanism of action of VNS is dependent upon afferent brainstem circuitry, which comprises a critical component of the Vagus Afferent Network (VagAN). To evaluate the association between brainstem afferent circuitry and seizure response, we retrospectively collected intraoperative data from sub-cortical recordings of somatosensory evoked potentials (SSEP) in 7 children with focal drug resistant epilepsy who had failed epilepsy surgery and subsequently underwent VNS. Using multivariate linear regression, we demonstrate a robust negative association between SSEP amplitude (p < 0.01), and seizure reduction. There was no association between SSEP latency and seizure outcomes. Our findings provide novel insights into the mechanism of VNS and inform our understanding of the importance of brainstem afferent circuitry within the VagAN for seizure responsiveness following VNS.