An acoustic dipole radiation model for magnetoacoustic tomography with magnetic induction （MAT-MI） is pro- posed, based on the analyses of one-dimensional tissue vibration, three-dimensional acoustic dipole radiatio...An acoustic dipole radiation model for magnetoacoustic tomography with magnetic induction （MAT-MI） is pro- posed, based on the analyses of one-dimensional tissue vibration, three-dimensional acoustic dipole radiation and acoustic waveform detection with a planar piston transducer. The collected waveforms provide information about the conductiv- ity boundaries in various vibration intensities and phases due to the acoustic dipole radiation pattern. Combined with the simplified back projection algorithm, the conductivity configuration of the measured layer in terms of shape and size can be reconstructed with obvious border stripes. The numerical simulation is performed for a two-layer cylindrical phantom model and it is also verified by the experimental results of MAT-MI for a tissue-like sample phantom. The proposed model suggests a potential application of conductivity differentiation and provides a universal basis for the further study of conductivity reconstruction for MAT-MI.展开更多
Based on the principles of the Hall effect for ultrasound excitation and wave propagation in a static magnetic field,the theory of ultrasound induced Hall voltage generation is derived in explicit formulae with consid...Based on the principles of the Hall effect for ultrasound excitation and wave propagation in a static magnetic field,the theory of ultrasound induced Hall voltage generation is derived in explicit formulae with consideration of the acoustic radiation for a planar transducer.It is proved by numerical simulations that the induced Hall voltage is mainly generated at the conductivity boundary and can be used to map the spatial variation of the conductivity value along the acoustic transmission path.Both the simulated Hall voltage and the reconstructed image show good agreement with the experimental results of Wen[Ultrasonic Imaging 20(1998)206,21(1999)186].The promising simulation results suggest the potential of implementing medical electrical impedance imaging by means of ultrasound induced Hall effect imaging.展开更多
基金Project supported by the National Basic Research Program of China （Grant No. 2011CB707900）, the National Natural Science Foundation of China （Grant No. 10974098）, the Natural Science Foundation of Jiangsu Province, China （Grant No. BK2009407）, and the Specialized Research Fund for Doctoral Program of High Education of China （Grant No. 20093207120003）.
文摘An acoustic dipole radiation model for magnetoacoustic tomography with magnetic induction （MAT-MI） is pro- posed, based on the analyses of one-dimensional tissue vibration, three-dimensional acoustic dipole radiation and acoustic waveform detection with a planar piston transducer. The collected waveforms provide information about the conductiv- ity boundaries in various vibration intensities and phases due to the acoustic dipole radiation pattern. Combined with the simplified back projection algorithm, the conductivity configuration of the measured layer in terms of shape and size can be reconstructed with obvious border stripes. The numerical simulation is performed for a two-layer cylindrical phantom model and it is also verified by the experimental results of MAT-MI for a tissue-like sample phantom. The proposed model suggests a potential application of conductivity differentiation and provides a universal basis for the further study of conductivity reconstruction for MAT-MI.
基金Supported by the National Natural Science Foundation of China(10974098)the Doctoral Fund of Ministry of Education of China(20093207120003).
文摘Based on the principles of the Hall effect for ultrasound excitation and wave propagation in a static magnetic field,the theory of ultrasound induced Hall voltage generation is derived in explicit formulae with consideration of the acoustic radiation for a planar transducer.It is proved by numerical simulations that the induced Hall voltage is mainly generated at the conductivity boundary and can be used to map the spatial variation of the conductivity value along the acoustic transmission path.Both the simulated Hall voltage and the reconstructed image show good agreement with the experimental results of Wen[Ultrasonic Imaging 20(1998)206,21(1999)186].The promising simulation results suggest the potential of implementing medical electrical impedance imaging by means of ultrasound induced Hall effect imaging.
