STIED: a deep learning model for the spatiotemporal detection of focal interictal epileptiform discharges with MEG.

Journal: Scientific reports
Published Date:

Abstract

Magnetoencephalography (MEG) allows the non-invasive detection of interictal epileptiform discharges (IEDs). Clinical MEG analysis in epileptic patients traditionally relies on the visual identification of IEDs, which is time consuming and partially subjective. Automatic, data-driven detection methods exist but show limited performance. Still, the rise of deep learning (DL)-with its ability to reproduce human-like abilities-could revolutionize clinical MEG practice. Here, we developed and validated STIED, a simple yet powerful supervised DL algorithm combining two convolutional neural networks with temporal (1D time-course) and spatial (2D topography) features of MEG signals inspired from current clinical guidelines. Our DL model enabled a successful identification of IEDs in patients suffering from focal epilepsy with frequent and high amplitude spikes (FE group), with high-performance metrics-accuracy, specificity, and sensitivity all exceeding 85%-when learning from spatiotemporal features of IEDs. This performance can be attributed to our handling of input data, which mimics established clinical MEG practice. Reverse engineering further revealed that STIED encodes fine spatiotemporal features of IEDs rather than their mere amplitude. The model trained on the FE group also showed promising results when applied to a separate group of presurgical patients with different types of refractory focal epilepsy, though further work is needed to distinguish IEDs from physiological transients. This proof-of-concept study represents a first step towards the use of STIED and DL algorithms in the routine clinical MEG evaluation of epilepsy.

Authors

  • Raquel Fernández-Martín
    Laboratoire de Neuroanatomie et de Neuroimagerie Translationnelles (LN2T), ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070, Brussels, Belgium. raquelfm.pt@gmail.com.
  • Alfonso Gijón
    Department of Mathematics, Universidad de Córdoba, 14014, Córdoba, Spain. agijon@uco.es.
  • Odile Feys
    Laboratoire de Neuroanatomie et de Neuroimagerie Translationnelles (LN2T), ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070, Brussels, Belgium.
  • Elodie Juvené
    Department of Pediatric Neurology, Hôpital Universitaire de Bruxelles (H.U.B), Hôpital Erasme, Université Libre de Bruxelles (ULB), 1070, Brussels, Belgium.
  • Alec Aeby
    Department of Pediatric Neurology, Hôpital Universitaire de Bruxelles (H.U.B), Hôpital Erasme, Université Libre de Bruxelles (ULB), 1070, Brussels, Belgium.
  • Charline Urbain
    Neuropsychology and Functional Neuroimaging Unit (UR2NF), Center for Research in Cognition and Neurosciences (CRCN), ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070, Brussels, Belgium.
  • Xavier De Tiège
    Laboratoire de Cartographie fonctionnelle du Cerveau, ULB Neuroscience Institute (UNI), Université libre de Bruxelles (ULB), Brussels, Belgium; Department of Functional Neuroimaging, Service of Nuclear Medicine, CUB Hôpital Erasme, Université libre de Bruxelles (ULB), Brussels, Belgium.
  • Vincent Wens
    Laboratoire de Neuroanatomie et de Neuroimagerie Translationnelles (LN2T), ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 1070, Brussels, Belgium.