中文摘要：

感应式磁声成像是一种新型功能成像技术,能够反映组织电导率变化信息。生物组织结构和电导率分布复杂,且电导率存在非突变的或者连续过渡的边界。为深入研究更为真实的生物组织电导率分布与变化特点,本研究从不规则的几何模型出发,建立了单线圈激励下的偏心球、正方体、椭球和电导率连续分布的球模型,借助有限元分析,研究仿真模型中的感应涡流分布并计算空间声场,应用时间反演法进行声源重建,同时分析了检测范围对重构图像的影响。仿真结果表明,感应式磁声成像能够有效地重构区分组织电特性的声源分布图像,探测器检测范围的有限性会使重构图像轮廓失真。本研究为感应式磁声成像实用技术的研究提供了较好的理论基础。

英文摘要：

Magnetoacoustic tomography with magnetic induction（MAT-MI） is a newly emerged functional imaging method and could reflect the conductivity difference of tissue.The structure and conductivity distribution of biological tissue are complex and the conductivity distribution have a continuous transition but not abrupt.In order to explore the conductivity distribution and variation characters in the real tissue,this paper established eccentric,ellipsoidal,cubic and conductivity continuous distribution spherical models with single coil stimulation based on the irregular geometrical model.Moreover,we applied the finite element analysis to study the distribution of the induced current and calculate acoustic pressure.The acoustic source was reconstructed with time reversal method and influence on image quality with limited detection range was analyzed.The results revealed that MAT-MI could effectively reconstruct acoustic source images and owing to the limited detection range images were easily subjected to distortion.In summary,the results could provide a better theoretical foundation for practical application.