基于广义反演理论和有限元法的电阻抗断层成像重建算法

Electrical impedance tomography reconstruction algorithm based on general inversion theory and finite element method.

作者信息

Mengxing T, Xiuzhen D, Mingxin Q, Feng F, Xuetao S, Fusheng Y

机构信息

Biomedical Engineering Department, Fourth Military Medical University, Xian, Shaanxi, People's Republic of China.

出版信息

Med Biol Eng Comput. 1998 Jul;36(4):395-8. doi: 10.1007/BF02523205.

DOI:10.1007/BF02523205

PMID:10198520

Abstract

A strict EIT reconstruction algorithm, the general inversion algorithm (GIA) is presented. To improve the noise performance, the algorithm is modified by attenuating the condition number of the forward matrix F and implemented using an improved FEM scheme, to obtain the 2D image of impedance change (dynamic image). This modified general inversion algorithm (MGIA) can be used on a larger dimension FEM model (248 elements) and is more practical than the GIA. When implementing this algorithm in computer simulation and in a physical phantom, it is found that the MGIA has a smaller reconstruction error than the currently used algorithms (equipotential-back-projection algorithm and filtered spectral expansion algorithm). With 0.1% white noise in the data, the algorithm can still reconstruct images of a complicated model. Further improvements are also discussed.

摘要

提出了一种严格的电阻抗断层成像（EIT）重建算法——通用反演算法（GIA）。为了提高噪声性能，通过衰减正向矩阵F的条件数对该算法进行了改进，并采用改进的有限元方法（FEM）实现，以获得阻抗变化的二维图像（动态图像）。这种改进的通用反演算法（MGIA）可用于更大尺寸的有限元模型（248个单元），比GIA更具实用性。在计算机模拟和物理模型中实现该算法时，发现MGIA的重建误差比目前使用的算法（等电位反投影算法和滤波谱扩展算法）更小。在数据中加入0.1%的白噪声时，该算法仍能重建复杂模型的图像。还讨论了进一步的改进措施。