Method and apparatus for enhanced flow imaging in b-mode ultrasound

摘要

A method and apparatus for ultrasonically imaging flow directly in B mode employs a sequence of pulses transmitted (38,24) to a transmit focal position, with the backscattered signals from this sequence being filtered (46) to remove echoes from stationary or slow-moving reflectors along the transmit path. The resulting flow signals are superimposed on a conventional B-mode vector and displayed. A B-mode flow image is formed by repeating this procedure for multiple transmit focal positions across the region of interest. The filtering is performed in slow time (along transmit firings) using a high-pass "wall" filter (e.g., an FIR filter (48)) with harmonic image feed-through and optionally B-mode (fundamental) feed-through. The resulting B-mode flow image has low clutter from stationary or slow-moving tissue or vessel walls, high resolution, high frame rate and flow sensitivity in all directions. <IMAGE>