Abstract：Objective To study the changes of electrical impedance spectra of brain tissue with time after ischemic brain injury,
so as to provide biophysics and methodological support for the application and optimization of electrical impedance
tomography (EIT) technology in the monitoring of cerebral ischemic injury. Methods The electrical impedance spectra
of rat brain after cerebral ischemia were measured in vivo by two-electrode method. The changes of brain electrical impedance
spectra with time after stroke were observed and analyzed. Results The electrical impedance of rat brain tissue increased
rapidly within the first 3 hours after ischemia, and the impedance value reached the highest point at 3 hours after ischemia,
and then the change was relatively smooth. The analysis of spectral characteristics showed that the maximum relative
resistivity change at 3 h after ischemia was 48.7%, which was occurred at 79.4 kHz. The observation of ultrastructure
of ischemia tissue at this stage showed that the end foot edema of astrocytes was obvious, which was consistent with
the increase of electrical impedance of brain tissue after ischemia. Conclusion After ischemia, the electrical impedance
characteristics of brain tissue will show different characteristics with the change of measuring time and frequency. The
optimization of measuring frequency is expected to further improve the sensitivity of EIT technique in the detection of
cerebral ischemic injury. The time-dependent electrical impedance of brain tissue is also expected to provide support for
the evaluation of the degree of cerebral ischemic injury, which lays a foundation for the diagnosis and monitoring of
ultra-early ischemic stroke by EIT imaging.
周怡敏a，陈真辉a，史学涛a，亢君君b，付峰a. 急性缺血条件下的动物脑部电阻抗特性变化规律的实验研究[J]. 中国医疗设备, 2019, 34(11): 34-38.
ZHOU Yimina, CHEN Zhenhuia, SHI Xuetaoa, KANG Junjunb, FU Fenga. Experimental Study on the Changes of Electrical Impedance Characteristics of Animal Brain
Under the Condition of Acute Ischemia. China Medical Devices, 2019, 34(11): 34-38.
