在体兔脑组织电阻抗频率特性测量及电阻抗断层成像(英文)  

In vivo measurement of the rabbit brain impedance frequency response and the elementary imaging of electrical impedance tomography

作　　者：吴小明[1] 董秀珍[1] 秦明新[1] 王跃民[2] 

机构地区：[1]解放军第四军医大学生物医学工程系医学电子工程教研室,陕西省西安市710032 [2]解放军第四军医大学基础部生理学教研室,陕西省西安市710032

出　　处：《中国临床康复》2005年第32期240-242,F0003,共4页Chinese Journal of Clinical Rehabilitation

基　　金：中国-以色列科学与战略研究开发专项资金合作研究项目(99M-0021426)~~

摘　　要：背景:电阻抗断层成像技术是对人体表施加无害电信号,体表测量其响应,用重构算法得到人体内部的电阻抗或其变化的分布图像。与现有的CT,MRI等技术相比,电阻抗断层成像技术具有实时性强、费用低廉、便于连续监测和功能成像等优势。目的:在体测量兔脑组织在缺血前后的电阻抗频率特性,并对缺血脑组织进行电阻抗断层成像技术,验证电阻抗断层成像技术对脑功能变化成像的可能性。设计:单一样本实验。单位:解放军第四军医大生物医学工程系医学电子工程教研室。材料:实验于2001-08/09在解放军第四军医大学生物医学工程系医学电子工程教研室电阻抗断层成像实验室完成。选择成年健康家兔10只用于实验。方法:采用颈总动脉结扎法制造脑缺血动物模型,对缺血前后的脑组织电阻抗特性进行在体测量。利用电阻抗断层成像系统对单侧脑组织供血变化进行成像。主要观察指标:①缺血前后的脑组织在0.1Hz～1MHz频率范围内电阻抗频率特性曲线。②单侧脑组织供血变化电阻抗断层成像结果。结果:1只家兔钻透硬脑膜,9只家兔结果进入分析。①在缺血脑损伤发生后,脑阻抗明显增大,在10Hz以下脑阻抗变化率可达75%,在1kHz～1MHz频率范围脑阻抗变化率约为15%且比较稳定。②初步的动态成像结果显示,脑组织供血变化一侧与其电阻率变化位置相一致。结论:缺血前后脑组织阻抗变化率满足成像要求,可以将其作为一个成像变量。BACKGROUND： Electrical impedance tomography （EIT） uses non-invasive signals to probe the human body and then detect the responses on the boundary of the body in order to reconstruct an impedance distribution inside the body. Compared to CT and MRI, EIT takes the advantages of realtime technique, lower eost and easiness for both continuous monitoring and functional imaging. OBJECTIVE： This study was designed to perform the in vivo measurement of the rabbit hrain impedance frequency response before and after ischemia. And it was to verify the feasibility of EIT in brain functional imaging by ischemia brain functional imaging using EIT. DESIGN： It was a single-sample experiment. SETTING： It was conducted at the Department of Medical Electronic Engineering, Faculty of Biomedical Engineering, Fourth Military Medical University of Chinese PLA. MATERIALS： This study was conducted at the Department of Medical Electronic Engineering, Faculty of Biomedical Engineering, Fourth Military Medical University of Chinese PI,A from August to September 2001 and 10 healthy rabbits were selected. METHODS： Cerebral ischemia animal model was made using carotid artery ligation. Then the in vivo measurement of the rabbit brain impedance frequency response before and after ischemia was performed. Dynamic unilateral brain blood supply was recorded using EIT imaging. MAIN OUTCOME MEASURES：① The rabbit brain tissue impedance curves were plot before and after ischemia in the frequency range from 0.1 Hz to 1 MHz.②Dynamic unilateral brain blood supply was recorded using EIT imaging RESULTS： Nine rabbits entered the statistical analysis and one was omitted for the damage of duramater in craniotomy. ①After ischemia, brain impedance increased significantly. The ratio of increasing impedance can be up to 75% at frequencies lower than 10 Hz. And in the range from 1 kHz to 1 MHz, the ratio showed a constant value of 15%.②The preliminary dynamic imaging showed that the changes in unilateral brain blood supply is accordant w

关 键 词：脸 电阻抗 体层摄影术 信号处理 计算机辅助 

分 类 号：R741[医药卫生—神经病学与精神病学]