Computational Study of Time Reversal Mirror Technique for Microwave-Induced Thermo-Acoustic Tomography

Abstract

Microwave-Induced Thermo-Acoustic Tomography (MITAT) is a promising technique in biomedical imaging. It has predominant advantages in both contrast and resolution compared with conventional microwave or ultrasound imaging system for malignant tumors. In this paper, Time Reversal Mirror (TRM) imaging technique based on numeric method Pseudo-Spectrum Time Domain (PSTD) for MITAT imaging is studied computationally. The proportion relationship between the deposited microwave energy and the induced thermo-acoustic initial source is deduced by analytic method. Due to the globe higher order character and the efficiency, the PSTD method is employed to implement the forward core of the TRM and to model the complex biologic tissue. In order to illustrate the performance of the TRM technique applied in MITAT, some thermo-acoustic objects with different initial pressure distributions are simulated, then designed and imaged by this technique to represent the complex biologic tissue case in a random media. Under the consideration of noise and the velocity parameter change of the model, the contrast and resolution of the images generated by using TRM technique based on PSTD method are also studied.