Preliminary research on monitoring of cerebral ischemia using electrical impedance tomography technique.

More than half of the stroke patients are cause by cerebral ischemia/ hypoxia, and it is by no means an easy affairs to detect ischemic tissue when it is rescuable by drug intervention using traditional imaging technique. The purpose of this paper is to testify the feasibility of monitoring cerebral ischemia. By a newly developed high precision data acquisition system and specially configured imaging method, a series of imaging monitoring experiments were performed on 8 Chinese local rabbits, who have been induced with cortical ischemia by photochemical method. This method of induce ischemia was confirmed by histopathological examination. The imaging results show that impedance in target area increased rapidly 7-20 minutes after the beginning of the irradiation during ischemia induce process, and will still change rapidly during and after the induction of ischemia. Unexpected impedance fluctuations were also seen in 6 out of 8 animals during this process. Therefore, EIT monitoring technique proved to be a rapid and sensitive way to detect cerebral ischemia in very earlier stage.