Abstract：The aim of this paper was to investigate the thermo-acoustic (TA) effect in magneto-acoustic tomography with magnetic induction (MAT-MI) and analyze the characteristics of distribution and amplitude of magneto-acoustic (MA) source and thermo-acoustic source.Expressions of MA and TA sources were established. The induced current distribution, MA+TA source distribution and sound pressure of the multi-layer conductivity simulation model were calculated by numerical simulation. The results of the two kinds of source distribution and reconstruction were compared. To verify the simulation model, MAT experimental platform was built, and the experiments of MA and TA were carried out with a conductive rubber ring. The amplitude and reconstruction results of MA and TA signals were compared and analyzed.Numerical simulation showed that MA source concentrated at the conductivity boundary, while TA source was widely distributed at both the boundary and the inside. The maximum value of MA source was 15 times of TA source. Phantom experiments showed that the peak to peak value of TA signal was a quarter of mixed signal. The reconstructed boundary of TA was fuzzy, while that of MA was clear but contained artifacts. The results of simulation and experiment proved that TA effect existed in MAT. The distribution of TA source and the amplitude relationship between MA and TA signals suggested that TA effect partly affected the result of MAT.
作者简介: # 中国生物医学工程学会会员 (Member,Chinese Society of Biomedical Engineering)
杨铭, 马任, 张顺起, 周晓青, 殷涛, 刘志朋. 感应式磁声成像中的磁热声效应研究[J]. 中国生物医学工程学报, 2020, 39(3): 295-302.
Yang Ming, Ma Ren, Zhang Shunqi, Zhou Xiaoqing, Yin Tao, Liu Zhipeng. Study on Thermo-Acoustic Effect in Magneto-Acoustic Tomography with Magnetic Induction. Chinese Journal of Biomedical Engineering, 2020, 39(3): 295-302.
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