基于椭圆几何模型的胸部电阻抗成像  

Electrical impedance tomography in chest based on the elliptical geometry model

作　　者：严佩敏[1] 曹永香[1] 

机构地区：[1]上海大学通信与信息工程学院,上海200444

出　　处：《电子测量技术》2016年第6期81-84,共4页Electronic Measurement Technology

摘　　要：电阻抗成像技术是通过测量生物体表面电压,计算生物体横截面的电阻抗分布。由于生物体的边界形状是各异的,尤其在胸部应用中,建立不同边界形状会影响成像的精度和清晰度,所以构建合适的边界形状是求解EIT问题的前提。根据实际视觉效果,椭圆几何比较符合胸部边界形状,由于圆形几何的构建和有限元划分相当成熟,本文通过保角变换方法将圆形转换为椭圆几何,并分别进行两种几何与原始胸部形状的分析比较,实验结果表明,在求解正问题时建立椭圆边界形状分析胸部结构精度高,在求解逆问题时重建误差小。Electrical impedance tomography （EIT ） is a medical imaging modality that is used to compute the conductivity distribution through measurements on the cross-section of a body part .As a result the boundary shape of the organisms is different ,building different boundary shape will affect the precision and clarity of imaging ,so to build a suitable boundary shape is the precondition of solving the forward problem of EIT ,especially in the chest .According to the actual visual effect ,the elliptical geometry conforms to the chest boundary shape ,due to the construction and finite element method of a circular shape is quite mature ,this article uses conformal mapping method convert circular to elliptical geometry ,and then analyzes and compares the two shapes respectively with the original chest geometry ,the results showed that to build elliptical geometry in analyzing the forward problem of chest structure has higher precision , in solving the inverse problem has smaller reconstruction error .

关 键 词：电阻抗成像技术 椭圆几何 保角变换 正问题 

分 类 号：TP806.1[自动化与计算机技术—检测技术与自动化装置]