基于个性化三维心脏-躯干模型的心磁正问题  

Magnetocardiogram forward problem based on personalized three-dimensional heart-torso model

作　　者：许炜炜 白明珠 林强[1,2] 胡正珲 Xu Wei-Wei;Bai Ming-Zhu;Lin Qiang;Hu Zheng-Hui(College of Science, Zhejiang University of Technology, Hangzhou 310023, China;Collaborative Innovation Center for Bio-Med Physics Information Technology,Zhejiang University of Technology, Hangzhou 310023, China)

机构地区：[1]浙江工业大学理学院,杭州310023 [2]浙江工业大学,生物医学物理协同创新中心,杭州310023

出　　处：《物理学报》2019年第17期308-317,共10页Acta Physica Sinica

基　　金：国家重点基础研究发展计划(批准号:2013CB329501);国家自然科学基金(批准号:81271645);浙江省自然科学基金(批准号:LY12H18004)资助的课题~~

摘　　要：建立了基于有限元法(FEM)的三维心磁正问题计算框架,以研究人体心脏电生理活动产生的磁场问题.首先对被试的心脏和躯干磁共振影像数据源进行三维个性化建模,获得心脏-躯干几何模型.其次结合心脏三维模型与修正的FitzHugh-Nagumo(FHN)方程研究由跨膜电位(TMP)产生的电兴奋在心脏内部的传导.随后利用躯干三维模型与准静态麦克斯韦方程,研究心脏电兴奋产生的生物电磁场在体内的传播过程,进而获得体表外的心脏磁场分布.心磁计算框架仿真结果显示,使用FEM的模型可以较好地模拟体表外磁场分布.一维FHN方程和直导线的简化模型数值结果分别与解析解呈现出较好的一致性,验证了该计算框架的可行性.综上,该框架成功地仿真了TMP在心脏内部的传播过程及其在体表外投影的磁场分布,这将有助于未来心磁逆问题求解的研究.In order to simulate the distribution of magnetic field generated by cardiac electrophysiological activities,a three-dimensional(3 D)computing framework of magnetocardiogram forward problem based on a finite element method(FEM)is proposed.First,the 3 D heart-torso geometry model is established from the 3 D reconstruction of magnetic resonance images.Then the modified FitzHugh-Nagumo(FHN)equation combined with 3 D cardiac geometry is used to investigate the propagation of transmembrane potential(TMP).In the end,quasi-static Maxwell equations and 3 D torso model are used to explore the propagation of the bioelectromagnetic field produced by TMP.In our calculation,the Galerkin finite element method is used.The results show that the FEM-model can simulate extracorporeal magnetic field.Further,numerical solutions of simplified models with the one-dimensional FHN equation and the straight wire are respectively consistent with the analytical solutions,which verifies the feasibility of the computing framework.In summary,this framework successfully simulates the cardiac TMP and extracorporeal magnetic field,which may conduce to the study of magnetocardiogram inverse problem.

关 键 词：心磁 FITZHUGH-NAGUMO方程 有限元法 跨膜电位 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术] R312[自动化与计算机技术—计算机科学与技术]