Microwave-excited ultrasound and thermoacoustic dual imaging

We designed a microwave-excited ultrasound (MUI) and thermoacoustic dual imaging system. Under the pulsed microwave excitation, the piezoelectric transducer used for thermoacoustic signal detection will also emit a highly directional ultrasonic beam based on the inverse piezoelectric effect. With this beam, the ultrasonic transmitter circuitry of the traditional ultrasound imaging (TUI) system can be replaced by a microwave source. In other words, TUI can be fully integrated into the thermoacoustic imaging system by sharing the microwave excitation source and the transducer. Moreover, the signals of the two imaging modalities do not interfere with each other due to the existence of the sound path difference, so that MUI can be performed simultaneously with microwave-induced thermoacoustic imaging. In the study, the performance characteristics and imaging capabilities of this hybrid system are demonstrated. The results indicate that our design provides one easy method for low-cost platform integration and has the potential to offer a clinically useful dual-modality tool for the detection of accurate diseases.