Kim Donghyeon, Seo Hyeon, Kim Hyoung-Ihl, Jun Sung Chan
School of Information and Communications, Gwangju Institute of Science and Technology, Gwangju, South Korea.
Department of Medical System Engineering, Gwangju Institute of Science and Technology, Gwangju, South Korea.
PLoS One. 2014 Sep 17;9(9):e108028. doi: 10.1371/journal.pone.0108028. eCollection 2014.
Subdural cortical stimulation (SuCS) is a method used to inject electrical current through electrodes beneath the dura mater, and is known to be useful in treating brain disorders. However, precisely how SuCS must be applied to yield the most effective results has rarely been investigated. For this purpose, we developed a three-dimensional computational model that represents an anatomically realistic brain model including an upper chest. With this computational model, we investigated the influence of stimulation amplitudes, electrode configurations (single or paddle-array), and white matter conductivities (isotropy or anisotropy). Further, the effects of stimulation were compared with two other computational models, including an anatomically realistic brain-only model and the simplified extruded slab model representing the precentral gyrus area. The results of voltage stimulation suggested that there was a synergistic effect with the paddle-array due to the use of multiple electrodes; however, a single electrode was more efficient with current stimulation. The conventional model (simplified extruded slab) far overestimated the effects of stimulation with both voltage and current by comparison to our proposed realistic upper body model. However, the realistic upper body and full brain-only models demonstrated similar stimulation effects. In our investigation of the influence of anisotropic conductivity, model with a fixed ratio (1∶10) anisotropic conductivity yielded deeper penetration depths and larger extents of stimulation than others. However, isotropic and anisotropic models with fixed ratios (1∶2, 1∶5) yielded similar stimulation effects. Lastly, whether the reference electrode was located on the right or left chest had no substantial effects on stimulation.
硬膜下皮质刺激（SuCS）是一种通过硬脑膜下的电极注入电流的方法，已知其在治疗脑部疾病方面有用。然而，很少有人研究如何精确应用SuCS以产生最有效的结果。为此，我们开发了一个三维计算模型，该模型代表了一个包括上胸部的解剖学逼真的大脑模型。利用这个计算模型，我们研究了刺激幅度、电极配置（单电极或桨状阵列）和白质电导率（各向同性或各向异性）的影响。此外，将刺激效果与另外两个计算模型进行了比较，包括一个解剖学逼真的仅大脑模型和代表中央前回区域的简化挤压平板模型。电压刺激的结果表明，由于使用多个电极，桨状阵列存在协同效应；然而，对于电流刺激，单电极更有效。与我们提出的逼真上身模型相比，传统模型（简化挤压平板）大大高估了电压和电流刺激的效果。然而，逼真的上身模型和仅全脑模型显示出相似的刺激效果。在我们对各向异性电导率影响的研究中，具有固定比例（1∶10）各向异性电导率的模型比其他模型产生更深的穿透深度和更大的刺激范围。然而，具有固定比例（1∶2、1∶5）的各向同性和各向异性模型产生相似的刺激效果。最后，参考电极位于右胸还是左胸对刺激没有实质性影响。
