magnetic source imagine; magnetoencephalography; temporal lobe epilepsy; optically pump magnetometer
Abstract :
[en] Cryogenic magnetoencephalography (MEG) has a lower yield in temporal lobe epilepsy (TLE) than in extratemporal lobe epilepsy. The advent of optically pumped magnetometers (OPMs) might change this situation thanks to on‐scalp MEG. This study aims to investigate the detection/localization accuracy of interictal epileptiform discharges (IEDs) using on‐scalp MEG in TLE and the added value of face‐OPMs. Eleven patients underwent a 1‐h MEG recording with OPMs placed both on the scalp (flexible cap, scalp‐OPMs) and on the face (glasseslike structure, face‐OPMs). Nine patients underwent cryogenic MEG. IED amplitude and signal‐to‐noise ratio (SNR) were compared when ≥10 IEDs were detected. A mean of 13 IEDs/patient were detected using on‐scalp MEG (mean amplitude = 3.3 pT, mean SNR = 9.4) and localized in the (medial, anterior, basal, lateral, posterior) temporal lobe. Amplitude and SNR were either higher or similar between on‐scalp and cryogenic MEG, with neural sources separated by 6–16 mm. In two patients, on‐scalp MEG source locations were confirmed by surgical resection cavity or stereoelectroencephalography. Face‐OPMs had a clear added value in one patient with anteromedial TLE. On‐scalp MEG can detect/localize IEDs in TLE. Face‐OPMs may have added value in patients with anterior/medial TLE and increase the spatial coverage of the temporal lobe. This study paves the way for the use of on‐scalp MEG in patients with refractory TLE.
Disciplines :
Neurology
Author, co-author :
Feys, Odile ; Department of Neurology, Hôpital Universitaire de Bruxelles (H.U.B.), Hôpital Erasme Université Libre de Bruxelles (ULB) Brussels Belgium ; Laboratoire de Neuroanatomie et Neuroimagerie Translationnelles, ULB Neuroscience Institute Université Libre de Bruxelles (ULB) Brussels Belgium
Wens, Vincent; Laboratoire de Neuroanatomie et Neuroimagerie Translationnelles, ULB Neuroscience Institute Université Libre de Bruxelles (ULB) Brussels Belgium ; Department of Translational Neuroimaging, Hôpital Universitaire de Bruxelles (H.U.B.), Hôpital Erasme Université Libre de Bruxelles (ULB) Brussels Belgium
Depondt, Chantal; Department of Neurology, Hôpital Universitaire de Bruxelles (H.U.B.), Hôpital Erasme Université Libre de Bruxelles (ULB) Brussels Belgium
Rikir, Estelle ; Université de Liège - ULiège > Département des sciences cliniques ; Department of Neurology, Hôpital Universitaire de Bruxelles (H.U.B.), Hôpital Erasme Université Libre de Bruxelles (ULB) Brussels Belgium
Gaspard, Nicolas; Department of Neurology, Hôpital Universitaire de Bruxelles (H.U.B.), Hôpital Erasme Université Libre de Bruxelles (ULB) Brussels Belgium ; Department of Neurology Yale University New Haven Connecticut USA
Van Paesschen, Wim; Department of Neurology Universitair Ziekenhuis Leuven, Katholieke Universiteit Leuven Leuven Belgium
Aeby, Alec; Department of Pediatric Neurology Hôpital Universitaire des Enfants Reine Fabiola, Hôpital Universitaire de Bruxelles (H.U.B.), Université Libre de Bruxelles (ULB) Brussels Belgium
Bodart, Olivier ; Université de Liège - ULiège > Département des sciences cliniques > Neurologie
Carrette, Evelien; Department of Neurology Universitair Ziekenhuis Gent, Universiteit Gent Ghent Belgium
Holmes, Niall; School of Physics and Astronomy Sir Peter Mansfield Imaging Centre, University of Nottingham Nottingham UK
Brookes, Matthew; School of Physics and Astronomy Sir Peter Mansfield Imaging Centre, University of Nottingham Nottingham UK
Ferez, Maxime; Laboratoire de Neuroanatomie et Neuroimagerie Translationnelles, ULB Neuroscience Institute Université Libre de Bruxelles (ULB) Brussels Belgium
Corvilain, Pierre; Laboratoire de Neuroanatomie et Neuroimagerie Translationnelles, ULB Neuroscience Institute Université Libre de Bruxelles (ULB) Brussels Belgium
De Tiège, Xavier ; Laboratoire de Neuroanatomie et Neuroimagerie Translationnelles, ULB Neuroscience Institute Université Libre de Bruxelles (ULB) Brussels Belgium ; Department of Translational Neuroimaging, Hôpital Universitaire de Bruxelles (H.U.B.), Hôpital Erasme Université Libre de Bruxelles (ULB) Brussels Belgium
FRIA - Fonds pour la Formation à la Recherche dans l'Industrie et dans l'Agriculture F.R.S.-FNRS - Fonds de la Recherche Scientifique Innoviris - Institut Bruxellois pour la Recherche et l'Innovation
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