中国物理B ›› 2017, Vol. 26 ›› Issue (8): 84301-084301.doi: 10.1088/1674-1056/26/8/084301

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Boundary normal pressure-based electrical conductivity reconstruction for magneto-acoustic tomography with magnetic induction

Ge-Pu Guo(郭各朴), He-Ping Ding(丁鹤平), Si-Jie Dai(戴思捷), Qing-Yu Ma(马青玉)   

  1. 1 Key Laboratory of Optoelectronics of Jiangsu Province, School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China;
    2 Honors College, Nanjing Normal University, Nanjing 210023, China
  • 收稿日期:2017-03-27 修回日期:2017-05-02 出版日期:2017-08-05 发布日期:2017-08-05
  • 通讯作者: Qing-Yu Ma E-mail:maqingyu@njnu.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11474166 and 11604156), the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20161013), the Postdoctoral Science Foundation of China (Grant No. 2016M591874), and the Priority Academic Program Development of Jiangsu Provincial Higher Education Institutions, China.

Boundary normal pressure-based electrical conductivity reconstruction for magneto-acoustic tomography with magnetic induction

Ge-Pu Guo(郭各朴)1, He-Ping Ding(丁鹤平)1, Si-Jie Dai(戴思捷)2, Qing-Yu Ma(马青玉)1   

  1. 1 Key Laboratory of Optoelectronics of Jiangsu Province, School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China;
    2 Honors College, Nanjing Normal University, Nanjing 210023, China
  • Received:2017-03-27 Revised:2017-05-02 Online:2017-08-05 Published:2017-08-05
  • Contact: Qing-Yu Ma E-mail:maqingyu@njnu.edu.cn
  • About author:0.1088/1674-1056/26/8/
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11474166 and 11604156), the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20161013), the Postdoctoral Science Foundation of China (Grant No. 2016M591874), and the Priority Academic Program Development of Jiangsu Provincial Higher Education Institutions, China.

摘要:

As a kind of multi-physics imaging approach integrating the advantages of electrical impedance tomography and ultrasound imaging with the improved spatial resolution and image contrast, magneto-acoustic tomography with magnetic induction (MAT-MI) is demonstrated to have the capability of electrical impedance contrast imaging for biological tissues with conductivity differences. By being detected with a strong directional transducer, abrupt pressure change is proved to be generated by the gradient of the induced Lorentz force along the force direction at conductivity boundary. A simplified boundary normal pressure (BNP)-based conductivity reconstruction algorithm is proposed and the formula for conductivity distribution inside the object with the clear physical meaning of pressure derivative, is derived. Numerical simulations of acoustic pressure and conductivity reconstruction are conducted based on a 2-layer eccentric cylindrical phantom model using Hilbert transform. The reconstructed two-dimensional conductivity images accord well with the model, thus successfully making up the deficiency of only imaging conductivity boundary in traditional MAT-MI. The proposed method is also demonstrated to have a spatial resolution of one wavelength. This study provides a new method of reconstructing accurate electrical conductivity and suggests the potential applications of MAT-MI in imaging biological tissues with conductivity difference.

关键词: magneto-acoustic tomography with magnetic induction, boundary normal pressure, conductivity reconstruction, pressure derivative, Hilbert transform

Abstract:

As a kind of multi-physics imaging approach integrating the advantages of electrical impedance tomography and ultrasound imaging with the improved spatial resolution and image contrast, magneto-acoustic tomography with magnetic induction (MAT-MI) is demonstrated to have the capability of electrical impedance contrast imaging for biological tissues with conductivity differences. By being detected with a strong directional transducer, abrupt pressure change is proved to be generated by the gradient of the induced Lorentz force along the force direction at conductivity boundary. A simplified boundary normal pressure (BNP)-based conductivity reconstruction algorithm is proposed and the formula for conductivity distribution inside the object with the clear physical meaning of pressure derivative, is derived. Numerical simulations of acoustic pressure and conductivity reconstruction are conducted based on a 2-layer eccentric cylindrical phantom model using Hilbert transform. The reconstructed two-dimensional conductivity images accord well with the model, thus successfully making up the deficiency of only imaging conductivity boundary in traditional MAT-MI. The proposed method is also demonstrated to have a spatial resolution of one wavelength. This study provides a new method of reconstructing accurate electrical conductivity and suggests the potential applications of MAT-MI in imaging biological tissues with conductivity difference.

Key words: magneto-acoustic tomography with magnetic induction, boundary normal pressure, conductivity reconstruction, pressure derivative, Hilbert transform

中图分类号:  (Acoustical measurement methods in biological systems and media)

  • 43.80.Ev
72.55.+s (Magnetoacoustic effects) 73.50.Rb (Acoustoelectric and magnetoacoustic effects)