开放式电阻抗成像建模及其仿真  

Modeling and simulation based on open electrical impedance tomography

作　　者：陈民铀[1] 张晓菊[1] 罗辞勇[1] 何为[1] 

机构地区：[1]重庆大学电气工程学院输配电装备及系统安全与新技术国家重点实验室,重庆400030

出　　处：《重庆大学学报（自然科学版）》2009年第7期731-735,共5页Journal of Chongqing University

基　　金：国家高技术发展(863计划)项目(2006AA02Z4B7)

摘　　要：为克服封闭式电阻抗成像电极位置不确定性引入的图像重构误差,采用固定电极阵列的开放式电阻抗成像(open electrical impedance tomography,OEIT)模型。将求解整个开放场域电磁场边值问题,近似转化为局部的虚拟场域。通过仿真实验选取有效边界参数和电极阵列结构。利用有限元法求解OEIT的正问题,采用一步牛顿法进行图像重构。实验结果表明OEIT能够探测到目标位置、区域以及电导率的变化,重构图像较清晰。OEIT在浅层体表具有较好的分辨率和定位准确度,有一定的临床应用价值。In order to improve the error in image reconstruction caused by changeable positions of the electrodes in closed electrical impedance tomography, we propose an open electrical impedance tomography （OEIT） model using fixed electrode array. The problem was approximately assumed to be a virtual field by defining certain local sensitive area instead of solving the boundary problem in the whole electromagnetic field strictly. Modeling and simulation of OEIT have been conducted to define reasonable boundary parameters and electrode array structure. The finite element method is used for forward computation while Newton one-step error reconstructor is used for image reconstruction. The target position, area and conductivity change can be reflected by the relative change of the boundary voltage and the reconstructed image is clear. Better resolution and positioning accuracy can be obtained in the shallower surface of the body by OEIT, so it is valuable in clinical applications.

关 键 词：电阻抗成像 开放式电阻抗成像 封闭式电阻抗成像 

分 类 号：TM152[电气工程—电工理论与新技术]