感应式磁声成像中的三维电磁场正逆问题研究

Three dimensional electromagnetic forward/inverse problems in magnetoacoustic tomography with magnetic induction

感应式磁声成像技术是近年来发展起来的一种新的电阻抗成像方法,是超声成像技术与传统电阻抗成像相结合的产物。本文基于电磁场基本理论,研究了感应式磁声成像中的电磁场正逆问题,推导了感应式磁声成像中的三维电磁场逆问题计算公式,提出一种不需要旋转静磁场的逆问题重建方法,建立了三维仿真模型并进行了数值计算实验。结果验证了该方法的正确性和可行性,得到了分辨率较高的电导率绝对值图像。

Magnetoacoustic tomography with magnetic induction （MAT-MI） is a new branch of impedance imaging, which combines ultrasonic technology with classic electrical impedance tomography （EIT）. Based on electromagnetic field theory, we researched on the 3-D simulation of MAT-MI, deducted the formula of forward and inverse problems, and set up a method of reconstruction without rotation of the static magnetic field. We solved the inverse problem by the method of algebra iteration. We validated the feasibility of this method, and obtained the images showing the absolute distribution of conductivity.