Microwave induced thermo-acoustic tomography (MITAT) has great potential in early breast cancer detection because it utilizes the advantages of both microwave imaging and ultrasound imaging. In this paper, we develop a fast and efficient simulation approach based on a hybrid method which combines finite integration time domain (FITD) method and pseudo-spectral time domain (PSTD) method is developed. By using this approach, energy deposition of biology tissue illuminated by electromagnetic fields can be accurately simulated. Meanwhile, acoustic properties of the tissue can be efficiently simulated as well. Compared to traditional methods, such as finite difference time domain (FDTD), et al, the developed method can well process real 3-D electromagnetic-acoustic complex models. Based on this approach, a MITAT model is created and some simulated results are analyzed. Furthermore, some real breast tissues are adopted to perform the thermo-acoustic imaging experiment. Comparisons between experimental and simulated results are made. The feasibility and effectiveness of the proposed approach are demonstrated by both numerical simulations and experimental results.
2. Guo, B., J. Li, H. Zmuda, and M. Sheplak, "Multifrequency microwave-induced thermal acoustic imaging for breast cancer detection," IEEE Transactions on Biomedical Engineering, Vol. 54, No. 11, 2000-2010, 2007.
3. Wang, X., D. R. Bauer, R. Witte, and H. Xin, "Microwave-induced thermoacoustic imaging model for potential breast cancer detection," IEEE Transactions on Biomedical Engineering, Vol. 59, No. 10, 2782-2791, 2012.
4. Guo, B., Y. W. Wang, J. Li, P. Stoica, and R. Wu, "Microwave imaging via adaptive beamforming methods for breast cancer detection," PIERS Online, Vol. 1, No. 3, 350-353, 2005.
5. Liao, K.-F., X.-L. Zhang, and J. Shi, "Fast 3-D microwave imaging method based on subaperture approximation," Progress In Electromagnetics Research, Vol. 126, 333-353, 2012.
6. Qi, Y., W. Tan, Y. Wang, W. Hong, and Y. Wu, "3D bistatic omega-K imaging algorithm for near range microwave imaging systems with bistatic planar scanning geometry," Progress In Electromagnetics Research, Vol. 121, 409-431, 2011.
7. Tan, W., W. Hong, Y. Wang, and Y. Wu, "A novel spherical-wave three-dimensional imaging algorithm for microwave cylindrical scanning geometries," Progress In Electromagnetics Research, Vol. 111, 43-70, 2011.
8. Giamalaki, M. I. and I. S. Karanasiou, "Enhancement of a microwave radiometry imaging system's performance using left handed materials," Progress In Electromagnetics Research, Vol. 117, 253-265, 2011.
9. Zhao, Z. Q., J. Song, X. Z. Zhu, J. G. Wang, J. N. Wu, Y. L. Liu, Z. P. Nie, and Q. H. Liu, "System development of microwave induced thermo-acoustic tomography and experiments on breast tumor," Progress In Electromagnetics Research, Vol. 134, 323-336, 2013.
10. Zhu, X. Z., Z. Q. Zhao, J. G. Wang, J. Song, and Q.-H. Liu, "Microwave induced thermal acoustic tomography for breast tumor based on compressive sensing ," IEEE Transactions on Biomedical Engineering, Vol. 60, No. 5, 1298-1307, May 2013.
11. Kruger, R. A., K. D. Miller, H. E. Reynolds, W. L. Kiser, D. R. Reinecke, and G. A. Kruger, "Breast cancer in vivo: Contrast enhancement with thermo-acoustic CT at 434MHz --- Feasibility study," Radiology, Vol. 216, No. 1, 279-283, Jul. 2000.
12. Geng, K. and L. V. Wang, "Scanning microwave-induced thermo-acoustic tomography: Signal, resolution, and contrast ," Med. Phys., Vol. 28, No. 1, 4-10, 2001.
13. Nie, L., D. Xing, Q. Zhou, D. Yang, and H. Guo, "Microwave-induced thermoacoustic scanning CT for high-contrast and noninvasive breast cancer imaging," Med. Phys., Vol. 35, No. 9, 4026-4032, Sep. 2008.
14. Xu, M. and L. V.Wang, "Time-domain reconstruction for thermo-acoustic tomography in a spherical geometry," IEEE Trans. Med. Imag., Vol. 21, No. 7, 814-822, Jul. 2002.
15. Razanksy, D., S. Kellnberger, and V. Ntziachristos, "Near-field radiofrequency thermoacoustic tomography with impulse excitation," Med. Phys., Vol. 37, No. 9, 4602-4607, 2010.
16. Kellnberger, S., A. Hajiaboli, D. Razansky, and V. Ntziachristos, "Near-field thermoacoustic tomography of small animals," Phys. Med. Biol., Vol. 56, No. 11, 3433-3444, 2011.
17. Bauer, D., X. Wang, J. Vollin, H. Xin, and R. Witte, "Spectroscopic thermoacoustic imaging of water and fat composition," Appl. Phys. Lett., Vol. 101, 033705, 2012.
18. University of Wisconsin, Computational Electromagnetics, 2007, Available: http://uwcem.ece.wisc.edu/home.htm.
19. Xie, Y., B. Guo, J. Li, G. Ku, and L. V. Wang, "Adaptive and robust methods of reconstruction (ARMOR) for thermoacoustic tomography," IEEE Transactions on Biomedical Engineering, Vol. 55, No. 12, 2741-2752, 2008.
20. Clemens, M. and T. Weiland, "Discrete electromagnetism with the finite integration technique," Progress In Electromagnetics Research, Vol. 32, 65-87, 2001.
21. Treeby, B. E. and B. T. Cox, "k-wave: MATLAB toolbox for the simulation and reconstruction of photo-acoustic wave fields," Journal of Biomedical Optics, Vol. 15, No. 2, 021314, 2010.
22. Liu, Q. H., "The pseudospectral time-domain (PSTD) algorithm for acoustic waves in absorptive media," IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, Vol. 45, No. 4, 1044-1055, 1998.
23. Cox, B. T., J. G. Laufer, K. P. Köstli, and P. C. Beard, "Experimental validation of photoacoustic k-space propagation models," Photons Plus Ultrasound: Imaging and Sensing 2004, Proc. SPIE 5320 , 238-248, 2004.
24. Weiwad, W., et al., "Direct measurement of sound velocity in various specimens of breast tissue," Invest. Radiol., Vol. 35, 721-726, 2000.
25. Mast, T. D., "Empirical relationship between acoustic parameters in human soft tissue ," Acoust. Res. Lett., Vol. 1, 37-42, 2009.
26. Fink, M. and C. Prada, "Acoustic time-reversal mirrors," Inv. Probl., Vol. 17, No. 1, 1-38, 2001.
27. Xu, Y. and L. V. Wang, "Time reversal and its application to tomography with diffracting sources," Phys. Rev. Lett., Vol. 92, No. 3, 1-4, 2004.
28. Chen, G. P. and Z. Q. Zhao, "Ultrasound tomography-guide TRM technique for breast tumor detecting in MITAT system," Journal of Electromagnetic Waves and Applications, Vol. 24, No. 13, 1459-1471, 2010.
29. Lazebnik, M., "A large-scale study of the ultrawideband microwave dielectric properties of normal, benign and malignant breast tissues obtained from cancer surgeries," Phys. Med. Biol., Vol. 52, No. 20, 6093-6115, 2007.