在体兔脑组织电阻抗频率特性测量及EIT初步成像  

In Vivo Measurement of Rabbits Brain Impedance Frequency Response and the Elementary Imaging of EIT

作　　者：吴小明[1] 董秀珍[1] 秦明新[1] 付峰[1] 王跃民[2] 尤富生[1] 向海燕[1] 刘锐岗[1] 史学涛[1] 

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

出　　处：《生物医学工程学杂志》2003年第1期49-51,共3页Journal of Biomedical Engineering

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-0 0 2 14 2 6)

摘　　要：通过频响分析仪 ,二电极法 ,对 10只家兔大脑缺血前后的脑阻抗频率特性进行在体测量 ,再尝试利用16电极 EIT成像系统 ,对兔脑阻抗的这一变化进行初步的动态成像实验。缺血模型采用的是颈总动脉结扎法 ,并经过单侧颈总动脉大脑供血区域染色实验 ,对缺血进行了验证。结果显示 ,在缺血脑损伤发生后 ,脑阻抗明显增大 ,在 10 Hz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 ,理论上完全满足成像要求 ,而且脑阻抗变化率可以作为一个成像变量 ;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 ,从而进一步证明利用 EIT技术对脑功能变化进行检测。The in vivo measurements of rabbit brain tissue impedance were taken under both normal and ischemic conditions by using two-electrode measurement method in the frequency range from 0.1 Hz to 1 MHz. The dynamic images about the resistivity of cerebral ischemia were reconstructed based on a 16-electrode system. The results of in vivo measurement showed that the ratio of impedance increased can be as high as 75% at frequencies lower than 10 Hz. In the range from 1 KHz to 1 MHz, the ratio showed a constant value of 15%. The electrical impedance tomography (EIT) images obtained suggested that the regions of impedance changes highly correspond to the position of ischemia. It is confirmed that the brain function change caused by local deficiency of blood can be detected and imaged by EIT method.

关 键 词：EIT 电阻抗断层成像 兔 脑 频率特性 

分 类 号：R310[医药卫生—基础医学]