基于Comsol的肺部电阻抗断层成像仿真研究
发布时间：2018-12-08 12:21
【摘要】：医学电阻抗成像技术(EIT)是当今生物医学界重要的研究领域之一。本文利用Comsol软件建立16电极圆形场仿真模型,分三种情况分析了有限元剖分的疏密对测量电极电压的影响,对场域内不同位置的成像对象做了正问题分析。利用共轭梯度图像重建算法,针对正问题仿真数据,利用Matlab编程实现对不同位置、不同大小的成像对象的图像重建。对共轭梯度法收敛性进行了分析,并采用设定的迭代停止条件,进行了圆形场重建实验,分别针对单个成像对象和两个成像对象进行分辨能力的评估。结合人体肺部组织的结构特征,利用人体胸部CT扫描图,建立更为精确的胸部仿真模型,实现了肺部连续呼吸过程中的图像重建,采用三种模型对呼吸过程中所重建的图像质量进行对比分析,得出了肺部呼吸过程中电导率和测量电极电压之间的变化关系。应用小波分析方法对肺功能成像过程中EIT电压矩阵数据进行分析,得出了心肺变化信息和频率特性,从中提取出了低频信息和高频信息,从而为临床研究提供依据。
[Abstract]:Medical Electrical Impedance Imaging (EIT) is one of the most important research fields in biomedical field. In this paper, a 16-electrode circular field simulation model is established by using Comsol software. The influence of the density of finite element method on the electrode voltage is analyzed in three cases, and the forward problem of the imaging object at different positions in the field is analyzed. Based on the conjugate gradient image reconstruction algorithm and the simulation data of positive problem, the image reconstruction of different positions and sizes of imaging objects is realized by Matlab programming. The convergence of the conjugate gradient method is analyzed and the circular field reconstruction experiment is carried out using the set iterative stopping conditions. The resolution of the single imaging object and the two imaging objects are evaluated respectively. Combined with the structural characteristics of human lung tissue, a more accurate chest simulation model was established by using the human chest CT scan, which realized the image reconstruction in the process of continuous lung respiration. Three models were used to compare and analyze the quality of the reconstructed images during respiration, and the relationship between electrical conductivity and electrode voltage was obtained. Wavelet analysis was used to analyze the EIT voltage matrix data during pulmonary function imaging. The changes and frequency characteristics of heart and lung were obtained, and the low frequency and high frequency information were extracted from the data, which provided the basis for clinical research.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.0;TP391.41
本文编号：2368340
[Abstract]:Medical Electrical Impedance Imaging (EIT) is one of the most important research fields in biomedical field. In this paper, a 16-electrode circular field simulation model is established by using Comsol software. The influence of the density of finite element method on the electrode voltage is analyzed in three cases, and the forward problem of the imaging object at different positions in the field is analyzed. Based on the conjugate gradient image reconstruction algorithm and the simulation data of positive problem, the image reconstruction of different positions and sizes of imaging objects is realized by Matlab programming. The convergence of the conjugate gradient method is analyzed and the circular field reconstruction experiment is carried out using the set iterative stopping conditions. The resolution of the single imaging object and the two imaging objects are evaluated respectively. Combined with the structural characteristics of human lung tissue, a more accurate chest simulation model was established by using the human chest CT scan, which realized the image reconstruction in the process of continuous lung respiration. Three models were used to compare and analyze the quality of the reconstructed images during respiration, and the relationship between electrical conductivity and electrode voltage was obtained. Wavelet analysis was used to analyze the EIT voltage matrix data during pulmonary function imaging. The changes and frequency characteristics of heart and lung were obtained, and the low frequency and high frequency information were extracted from the data, which provided the basis for clinical research.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.0;TP391.41
【参考文献】
相关期刊论文 前10条
1 董秀珍,秦明新,汤孟兴,史学涛,尤富生,刘锐岗;电阻抗断层成像系统及重构算法[J];第四军医大学学报;1999年03期
2 侯卫东,莫玉龙;静态阻抗断层图像重建新方法[J];电子学报;2003年07期
3 叶华俊,刘华锋,鲍超;基于小波变换的MR图像的去噪处理[J];光电工程;2003年01期
4 杨军,彭承琳,吴宝明;小波分析在医学中的应用[J];国外医学.生物医学工程分册;2002年02期
5 贾中云;小波变换及其数字图像处理的应用[J];杭州师范学院学报(自然科学版);2003年02期
6 史学涛;霍旭阳;尤富生;付峰;刘锐岗;徐灿华;董秀珍;;颅内出血电阻抗成像系统及初步动物实验[J];航天医学与医学工程;2007年01期
7 王伟;李章勇;官方勇;刘纯伦;方晓杰;任超世;;功能性消化不良胃动力信息检测与评价[J];航天医学与医学工程;2009年04期
8 唐化勇,牟永阁,杨常运,崔长安;生物电阻抗成像技术在医学中的应用[J];第四军医大学吉林军医学院学报;2000年03期
9 侯卫东,莫玉龙;电阻抗成象中求解反问题的新方法[J];计算机工程;2001年05期
10 米晨,魏凤兰;Haar小波变换在图像处理中的应用[J];宁夏工程技术;2003年01期
相关硕士学位论文 前2条
1 班东坡;人体电阻抗测量系统设计[D];天津大学;2004年
2 唐磊;电阻抗断层成像算法研究及系统软件设计[D];天津大学;2006年
，本文编号：2368340
本文链接：https://www.wllwen.com/yixuelunwen/swyx/2368340.html
