Multi-physics modeling of thermoacoustic pulse generation and propagation during pulsed microwave ablation of tissue.

Microwave-induced thermoacoustic (TA) imaging is a potential alternative to conventional real-time imaging methods for monitoring microwave ablation (MWA). In this study, we develop a multi-physics model for the generation and propagation of microwave-induced TA signals during pulsed MWA. Our model couples electromagnetics, heat transfer, and acoustics physics. We compare simulation and experimental results for a pulsed MWA system wherein a coaxial MWA antenna is used to heat water. The simulated and experimentally measured TA signals for this configuration are in good qualitative agreement. This multi-physics modeling tool is valuable for understanding the fundamentals of TA signal generation and propagation from within an evolving ablation zone.