Thermoacoustic imaging for handheld medical diagnostic and security screening applications

Stanford researchers have demonstrated the use of a coherent frequency-domain technique in microwave thermoacoustic imaging, which significantly improves signal-to-noise ratio (SNR) and reduces peak-power requirements without sacrificing resolution or other performance metrics.

These advantages enable portable, handheld thermoacoustic (TA) devices benefitting various medical diagnostic and screening needs. The proposed systems are implemented with solid-state electronics (as opposed to bulky vacuum sources) and open the way to a new generation of hand-held and even battery-operated screening tools. The team obtained TA images of multilayer relatively complex muscle-fat structures and believes that these are the first TA images obtained with solid-state electronic sources.

Figure

Figure Description (a) Pork belly tissue used in the experiment. (b) 2D raw matched filtering image. (c) 1-D matched-filtering result between measured signal and transmit reference signal. (d) Reconstructed image using FD-SAR. In the figures, A–C denote the top skin, middle muscle, and bottom muscle layers.

Stage of Research
Proof-of-concept
Proposed frequency-domain TA method demonstrated a sufficient soft-tissue contrast and resolution with a pork belly sample of layered structure