Localization of interictal spikes and high frequency oscillations (HFO) using magnetoencephalography (MEG)

Abstract

Event Abstract Back to Event Localization of interictal spikes and high frequency oscillations (HFO) using magnetoencephalography (MEG) Vahe Poghosyan1* 1 King Fahad Medical City, Department of Neurophysiology, National Neuroscience Institute, Saudi Arabia Epidemiological data show that about 40% of the patients with epilepsy are refractory to pharmacological treatment. In many such patients with focal epilepsy, an alternative therapeutic option of choice is the surgical resection of the epileptogenic zone. At present, a variety of diagnostic tools (e.g. analysis of seizure semiology, electrophysiological and neuroimaging tools, functional testing etc.) are used to define the different epilepsy-related cortical zones (symptomatogenic, irritative, seizure onset and functional deficit zones, and epileptogenic lesion), each of which indexes to a certain extent the location and boundaries of the epileptogenic zone. Recently, high frequency oscillations (HFO, 80 – 500 Hz) have been proposed as accurate biomarkers of the epileptogenic zone in intracranial electroencephalography recordings (Jacobs et al. 2012). Magnetoencephalography (MEG) substantially contributes to the pre-surgical evaluation of patients with focal epilepsy. Currently, its primary application is to localize the cortical sources of interictal spikes (irritative zone) as an estimate for the epileptogenic zone. Recent studies have shown that MEG can also be used to identify and localize sources of HFOs (Papadelis et al., 2009; Rampp et al., 2010). Accurate identification and localization of MEG HFOs can provide an important non-invasive biomarker for epileptogenicity. We have used several source localization methods to estimate and compare the sources of MEG interictal spikes and HFOs, and correlate them with the clinical information and post-surgical outcome. In this presentation, I will describe the results of this analysis and provide relevant recommendations. References Jacobs J., Staba R., Asano E., Otsubo H., Wu J.Y., Zijlmans M., Mohamed I., Kahane P., Dubeau F., Navarro V., and Gotman J. (2012). High-frequency oscillations (HFOs) in clinical epilepsy. Progress in neurobiology, 98: 302–315 Papadelis C., Poghosyan V., Fenwick P.B.C., and Ioannides A.A. (2009). MEG’s ability to localize accurately weak transient neural sources. Clinical Neurophysiology, 120: 1958–1970 Rampp S., Kaltenhäuser M., Weigel D., Buchfelder M., Blümcke I., Dörfler A., and Stefan, H. (2010). MEG correlates of epileptic high gamma oscillations in invasive EEG. Epilepsia, 51: 1638–1642. Keywords: Epilepsy, interictal epileptiform discharges, interictal spikes, Magnetoencephalography (MEG), high frequency oscillation Conference: SAN2016 Meeting, Corfu, Greece, 6 Oct - 9 Oct, 2016. Presentation Type: Oral Presentation in the Symposium Epilepsy and Sleep Topic: Symposium Epilepsy and Sleep Citation: Poghosyan V (2016). Localization of interictal spikes and high frequency oscillations (HFO) using magnetoencephalography (MEG). Conference Abstract: SAN2016 Meeting. doi: 10.3389/conf.fnhum.2016.220.00122 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 01 Aug 2016; Published Online: 01 Aug 2016. * Correspondence: Dr. Vahe Poghosyan, King Fahad Medical City, Department of Neurophysiology, National Neuroscience Institute, Riyadh, Saudi Arabia, vpoghosyan@kfmc.med.sa Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Vahe Poghosyan Google Vahe Poghosyan Google Scholar Vahe Poghosyan PubMed Vahe Poghosyan Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.