Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA.
IEEE Trans Med Imaging. 2013 Mar;32(3):619-27. doi: 10.1109/TMI.2013.2239656. Epub 2013 Jan 11.
Magnetoacoustic tomography with magnetic induction (MAT-MI) is a technique proposed to reconstruct the conductivity distribution in biological tissue at ultrasound imaging resolution. A magnetic pulse is used to generate eddy currents in the object, which in the presence of a static magnetic field induces Lorentz force based acoustic waves in the medium. This time resolved acoustic waves are collected with ultrasound transducers and, in the present work, these are used to reconstruct the current source which gives rise to the MAT-MI acoustic signal using vector imaging point spread functions. The reconstructed source is then used to estimate the conductivity distribution of the object. Computer simulations and phantom experiments are performed to demonstrate conductivity reconstruction through vector source imaging in a circular scanning geometry with a limited bandwidth finite size piston transducer. The results demonstrate that the MAT-MI approach is capable of conductivity reconstruction in a physical setting.
磁感应磁共振层析成像(MAT-MI)是一种在超声成像分辨率下重建生物组织电导率分布的技术。磁脉冲用于在物体中产生涡流,在存在静磁场的情况下,在介质中感应基于洛伦兹力的声波。使用超声换能器收集这些时变声波,在本工作中,使用矢量成像点扩散函数来重建产生 MAT-MI 声信号的电流源。然后使用重建的源来估计物体的电导率分布。进行了计算机模拟和体模实验,以证明在具有有限带宽的有限尺寸活塞换能器的圆形扫描几何形状中通过矢量源成像进行电导率重建的能力。结果表明,MAT-MI 方法能够在物理环境中进行电导率重建。