Power Doppler-Based Shear Wave Speed Estimation via Spatial Interference Patterns

Research in ultrasound elastography often relies on raw radio-frequency (RF) data to reconstruct shear wave speed (SWS) maps. However, many portable, cost-effective ultrasound devices, which are suitable in low-resource or rural settings, are limited to providing B-mode and Power Doppler (PD) data. This work establishes a proportionality between PD signal intensity and local tissue vibration amplitude, thereby enabling SWS map estimation from PD data. For this purpose, raw and power Doppler (PD) data from phantoms were analyzed using the interference patterns generated in the Crawling Waves Sonoelastography approach. A motion estimation algorithm was applied to the raw data, and subsequently, both the motion-estimated raw data and the PD data were processed using estimators based on the Short-Time Fourier Transform and the Continuous Wavelet Transform to estimate the SWS. The results show that the reconstruction of the SWS using PD provides comparable results to using raw data.