Bai S, Gálvez V, Dokos S, Martin D, Bikson M, Loo C
Department of Electrical and Computer Engineering, Technische Universität München, 80333 München, Germany; Graduate School of Biomedical Engineering, Faculty of Engineering, University of New South Wales (UNSW), NSW 2052, Australia.
School of Psychiatry, UNSW, NSW 2052, Australia; Black Dog Institute, NSW 2031, Australia.
Eur Psychiatry. 2017 Mar;41:21-29. doi: 10.1016/j.eurpsy.2016.09.005. Epub 2017 Feb 3.
Extensive clinical research has shown that the efficacy and cognitive outcomes of electroconvulsive therapy (ECT) are determined, in part, by the type of electrode placement used. Bitemporal ECT (BT, stimulating electrodes placed bilaterally in the frontotemporal region) is the form of ECT with relatively potent clinical and cognitive side effects. However, the reasons for this are poorly understood.
This study used computational modelling to examine regional differences in brain excitation between BT, Bifrontal (BF) and Right Unilateral (RUL) ECT, currently the most clinically-used ECT placements. Specifically, by comparing similarities and differences in current distribution patterns between BT ECT and the other two placements, the study aimed to create an explanatory model of critical brain sites that mediate antidepressant efficacy and sites associated with cognitive, particularly memory, adverse effects.
High resolution finite element human head models were generated from MRI scans of three subjects. The models were used to compare differences in activation between the three ECT placements, using subtraction maps.
In this exploratory study on three realistic head models, Bitemporal ECT resulted in greater direct stimulation of deep midline structures and also left temporal and inferior frontal regions. Interpreted in light of existing knowledge on depressive pathophysiology and cognitive neuroanatomy, it is suggested that the former sites are related to efficacy and the latter to cognitive deficits. We hereby propose an approach using binarised subtraction models that can be used to optimise, and even individualise, ECT therapies.
广泛的临床研究表明，电休克治疗（ECT）的疗效和认知结果部分取决于所使用的电极放置类型。双侧颞部ECT（BT，刺激电极双侧放置在前颞叶区域）是ECT的一种形式，具有相对较强的临床和认知副作用。然而，其原因尚不清楚。
本研究使用计算模型来研究BT、双额部（BF）和右侧单侧（RUL）ECT（目前临床上最常用的ECT放置方式）之间大脑兴奋的区域差异。具体而言，通过比较BT ECT与其他两种放置方式之间电流分布模式的异同，该研究旨在创建一个关键脑区的解释模型，这些脑区介导抗抑郁疗效以及与认知，特别是记忆不良反应相关的区域。
从三名受试者的MRI扫描生成高分辨率有限元人头模型。使用减法图，利用这些模型比较三种ECT放置方式之间的激活差异。
在这项对三个逼真头部模型的探索性研究中，双侧颞部ECT对深部中线结构以及左侧颞叶和额下回区域产生了更大的直接刺激。根据现有的抑郁病理生理学和认知神经解剖学知识进行解释，表明前者与疗效相关，后者与认知缺陷相关。我们在此提出一种使用二值化减法模型的方法，该方法可用于优化甚至个性化ECT治疗。
