Impact of modeled field of view in electroconvulsive therapy current flow simulations

Frontiers in Psychiatry

Psychiatry

Paula Pascoal-Faria¹  Christopher C. Abbott²  Zhi-De Deng³  Alexander Guillen⁴  Dennis Q. Truong⁴  Yu Huang⁴  Abhishek Datta⁵ 

[1] Department of Mathematics ESTG and CDRSP Polytechnic Institute of Leiria, Leiria, Portugal;Department of Psychiatry, University of New Mexico, Albuquerque, NM, United States;Noninvasive Neuromodulation Unit, Experimental Therapeutics and Pathophysiology Branch, National Institute of Mental Health, National Institute of Health, Bethesda, MD, United States;Research and Development, Soterix Medical, Woodbridge, NJ, United States;Research and Development, Soterix Medical, Woodbridge, NJ, United States;City College of New York, New York, NY, United States;

关键词: ECT;    electroconvulsive therapy;    extent;    human head model;    validation;    simulation;    MRI;   

DOI  :  10.3389/fpsyt.2023.1168672

 received in 2023-02-17, accepted in 2023-04-25,  发布年份 2023

来源: Frontiers

【 摘 要 】

BackgroundThe field of view (FOV) considered in MRI-guided forward models of electroconvulsive therapy (ECT) are, as expected, limited to the MRI volume collected. Therefore, there is variation in model extent considered across simulation efforts. This study examines the impact of FOV on the induced electric field (E-field) due to two common electrode placements: right unilateral (RUL) and bilateral (BL).MethodsA full-body dataset was obtained and processed for modeling relevant to ECT physics. Multiple extents were derived by truncating from the head down to four levels: upper head (whole-brain), full head, neck, and torso. All relevant stimulation and focality metrics were determined. The differences in the 99th percentile peak of stimulation strength in the brain between each extent to the full-body (reference) model were considered as the relative error (RE). We also determine the FOV beyond which the difference to a full-body model would be negligible.ResultsThe 2D and 3D spatial plots revealed anticipated results in line with prior efforts. The RE for BL upper head was ~50% reducing to ~2% for the neck FOV. The RE for RUL upper head was ~5% reducing to subpercentage (0.28%) for the full-head FOV. As shown previously, BL was found to stimulate a larger brain volume—but restricted to the upper head and for amplitude up to ~480 mA. To some extent, RUL stimulated a larger volume. The RUL-induced volume was larger even when considering the neural activation threshold corresponding to brief pulse BL if ECT amplitude was >270 mA. This finding is explained by the BL-induced current loss through the inferior regions as more FOV is considered. Our result is a departure from prior efforts and raises questions about the focality metric as defined and/or inter-individual differences.ConclusionOur findings highlight that BL is impacted more than RUL with respect to FOV. It is imperative to collect full-head data at a minimum for any BL simulation and possibly more. Clinical practice resorts to using BL ECT when RUL is unsuccessful. However, the notion that BL is more efficacious on the premise of stimulating more brain volume needs to be revisited.

【 授权许可】

Unknown   
Copyright © 2023 Guillen, Abbott, Deng, Huang, Pascoal-Faria, Truong and Datta.