Developing microwave-induced thermoacoustic tomography: System, application, and reconstruction

A microwave-induced thermoacoustic imaging (MITAT) system is a non-destructive physical medical imaging method that combines the advantages of the high contrast of microwave imaging and the high resolution of ultrasound imaging. It uses the microwave as the excitation source and ultrasound as the information carrier. When different kinds of biological tissue absorb electromagnetic energy, it results in localized temperature rises. The thermal expansion will induce ultrasonic signals (i.e., thermoacoustic signals) known as the thermoacoustic effect. The microwave absorption image of the sample can be reconstructed by algorithm processing. The MITAT contrast depends on different dielectric parameters of different kinds of tissue. We introduce the developed system and its application. In addition, the challenges and prospects of the MITAT for further development are argued.