Visualization of the electric field evoked by transcranial electric stimulation during a craniotomy using the finite element method
Visualization of the electric field evoked by transcranial electric stimulation during a craniotomy using the finite element method
复制标题
使用有限元法可视化开颅手术期间经颅电刺激引起的电场
DOI：
10.1016/j.jneumeth.2015.09.014
复制
发表时间：
2015
影响因子：
3
通讯作者：
Kazunari Yoshida
中科院分区：
文献类型：
--
作者：
Ryosuke Tomio;T. Akiyama;Tomo Horikoshi;T. Ohira;Kazunari Yoshida
经颅运动诱发电位（tMEP）比皮层运动诱发电位（cMEP）更容易监测，但tMEP的准确性不如cMEP。开颅手术和脑脊液水平的变化一定会影响电流的扩散。这些变化会影响准确性。本研究的目的是探讨影响颅骨变形和脑脊液（CSF）减少tMEP监测额颞craniotomy.MethodsWe使用有限元方法可视化的电场在大脑中，这是由经颅电刺激，使用现实的三维头部模型开发的T1加权图像。尽可能准确地分离头部5层的表面。我们建立了3种脑型和5种开颅手术模型。当CSF层较厚时，开颅术期间CSF体积的减少和CSF表面水平的降低对电场有重大影响。当脑脊液层较薄且颅骨和大脑之间的距离较短时，开颅手术对电场的影响大于CSF的降低，与现有方法比较，迄今为止文献中没有报道使用3-结论我们的主要发现是大脑中的电场强度受厚度变化的影响最大和CSF层的体积。
BackgroundTranscranial MEP (tMEP) monitoring is more readily performed than cortical MEP (cMEP), however, tMEP is considered as less accurate than cMEP. The craniotomy procedure and changes in CSF levels must affect current spread. These changes can impair the accuracy. The aim of this study was to investigate the influence of skull deformation and cerebrospinal fluid (CSF) decrease on tMEP monitoring during frontotemporal craniotomy.MethodsWe used the finite element method to visualize the electric field in the brain, which was generated by transcranial electric stimulation, using realistic 3-dimensional head models developed from T1-weighted images. Surfaces of 5 layers of the head were separated as accurately as possible. We created 3 brain types and 5 craniotomy models.ResultsThe electric field in the brain radiates out from the cortex just below the electrodes. When the CSF layer is thick, a decrease in CSF volume and depression of CSF surface level during the craniotomy has a major impact on the electric field. When the CSF layer is thin and the distance between the skull and brain is short, the craniotomy has a larger effect on the electric field than the CSF decrease.Comparison with existing methodSo far no report in the literature the electric field during intraoperative tMEP using a 3-dimensional realistic head model.ConclusionOur main finding was that the intensity of the electric field in the brain is most affected by changes in the thickness and volume of the CSF layer.