A fast microwave-induced thermoacoustic tomography system for imaging of biological tissues

We developed a fast microwave-induced thermoacoustic tomography system based on a 320-element phase-controlled linear transducer array. A 1.2GHz n-microwave generator transmits microwave with pulse duration of 0.5 us and an incident energy density of 0.45 mJ/cm(2). Compared to single transducer collection, the system with multi-element linear transducer array can eliminate the mechanical rotation of the transducer, so can effectively reduce the image blurring and improve the image resolution. Using phase-controlled technique to collect thermoacoustic signals, the data need not be averaged because of the high signal-to-noise ratio, resulting in the total data acquisition time of less than 5 s. The system thus provide a rapid and reliable approach to thermoacoustic imaging, which can potentially be developed as a powerful diagnostic tool for early-stage breast caners.