Ultrafast Doppler imaging of micro-bubbles

Plane-wave synthetic ultrasound considerably increases the imaging frame rate, which in turn can be used to improve the SNR or the frequency resolution of Doppler estimators. Ultrafast imaging also allows the implementation of bubble selective multi-pulse imaging sequences, such as pulse inversion, at frame rates sufficient for Doppler processing. It will be demonstrated in an in-vivo rabbit kidney that non-linear contrast enhanced Doppler permits the real-time segmentation of fast flow (arteries and veins), from the slow moving flow in capillaries, using a Doppler frequency filters analogous to conventional wall-filters.