Personalized tDCS for Focal Epilepsy—A Narrative Review: A Data-Driven Workflow Based on Imaging and EEG Data

Abstract

Conventional transcranial electric stimulation(tES) using standard anatomical positions for the electrodes and standard stimulation currents is frequently not sufficiently selective in targeting and reaching specific brain locations, leading to suboptimal application of electric fields. Recent advancements in in vivo electric field characterization may enable clinical researchers to derive better relationships between the electric field strength and the clinical results. Subject-specific electric field simulations could lead to improved electrode placement and more efficient treatments. Through this narrative review, we present a processing workflow to personalize tES for focal epilepsy, for which there is a clear cortical target to stimulate. The workflow utilizes clinical imaging and electroencephalography data and enables us to relate the simulated fields to clinical outcomes. We review and analyze the relevant literature for the processing steps in the workflow, which are the following: tissue segmentation, source localization, and stimulation optimization. In addition, we identify shortcomings and ongoing trends with regard to, for example, segmentation quality and tissue conductivity measurements. The presented processing steps result in personalized tES based on metrics like focality and field strength, which allow for correlation with clinical outcomes.

Targeted and optimized multi-channel transcranial direct current stimulation for focal epilepsy: An N-of-1 trial

“…The goal of reducing epileptic activity non-invasively was successfully achieved, as shown by a double-blinded sham-controlled stimulation experiment. The success of the optimization is dependent on the targeting accuracy with regard to both target location and target orientation (Dmochowski et al, 2013;Zulkifly et al, 2022;Khan et al, 2023) as well as on the idiosyncrasies of the individual head volume conductor model (Datta et al, 2010;Kasten et al, 2019;Khan et al, 2023;Beumer et al, 2022). Here, we targeted by combined EEG/MEG (EMEG) source analysis using the different sensitivity profiles and complementary information contained in both modalities (Dassios et al, 2007;Aydin et al, 2017;Ebersole and Wagner, 2018;Duez et al, 2019;Piastra et al, 2021).…”

Historical background and modern aspects of application transcranial micropolarization in epilepsy

“…Все перечисленные особенности постоянного тока низкой интенсивности вызывают у исследователей растущий интерес к его лечебным свойствам. Если в 2010 году ключевое слово tDCS присутствовало в 130 научных публикациях, то в 2020 году оно обнаруживается уже в 962 статьях [25].…”