Detection of acute cerebral hemorrhage in rabbits by magnetic induction.

Author: Sun J1, Jin G1, Qin MX1, Wan ZB2, Wang JB3, Wang C3, Guo WY3, Xu L1, Ning X1, Xu J1, Pu XJ1, Chen MS1, Zhao HM2.
Affiliation: 1College of Biomedical Engineering and Medical Imaging, Third Military Medical University, Chongqing, China, College of Biomedical Engineering and Medical Imaging, Third Military Medical University, Chongqing, China. 2Experimental Animal Center, Third Military Medical University, Chongqing, China, Experimental Animal Center, Third Military Medical University, Chongqing, China. 3College of Electronic Engineering, Xidian University, Xi'an, China, College of Electronic Engineering, Xidian University, Xi'an, China.
Conference/Journal: Braz J Med Biol Res.
Date published: 2014 Feb
Other: Volume ID: 47 , Issue ID: 2 , Pages: 144-50 , Special Notes: doi: 10.1590/1414-431X20132978 , Word Count: 234



Acute cerebral hemorrhage (ACH) is an important clinical problem that is often monitored and studied with expensive devices such as computed tomography, magnetic resonance imaging, and positron emission tomography. These devices are not readily available in economically underdeveloped regions of the world, emergency departments, and emergency zones. We have developed a less expensive tool for non-contact monitoring of ACH. The system measures the magnetic induction phase shift (MIPS) between the electromagnetic signals on two coils. ACH was induced in 6 experimental rabbits and edema was induced in 4 control rabbits by stereotactic methods, and their intracranial pressure and heart rate were monitored for 1 h. Signals were continuously monitored for up to 1 h at an exciting frequency of 10.7 MHz. Autologous blood was administered to the experimental group, and saline to the control group (1 to 3 mL) by injection of 1-mL every 5 min. The results showed a significant increase in MIPS as a function of the injection volume, but the heart rate was stable. In the experimental (ACH) group, there was a statistically significant positive correlation of the intracranial pressure and MIPS. The change of MIPS was greater in the ACH group than in the control group. This high-sensitivity system could detect a 1-mL change in blood volume. The MIPS was significantly related to the intracranial pressure. This observation suggests that the method could be valuable for detecting early warning signs in emergency medicine and critical care units.
PMID: 24519130