Shear wave speed measurement using repeated short push pulses

Measurement of shear wave propagation speed in tissues has clinical significance of indicating tissue stiffness and health state. Shear waves are usually produced by a high voltage, long duration ultrasound push beam. Many ultrasound scanners cannot produce such push beams due to power droop of the transmit circuitry. We propose using repeated short push pulses instead to generate shear waves. The waveform of such shear wave is separated into a push and a release shear wave as the collective push duration increases. Shear wave magnitudes and speeds in phantoms produced by different numbers and repetition intervals of short pulses were studied and the speeds were compared with 1D transient elastography results. The method was further validated using in vivo biceps measurements from a healthy volunteer. Results show accurate shear wave speed can be measured from shear waves produced by multiple short push pulses. Such short Doppler-like pulses could be used by conventional and low-end ultrasound scanners to do shear wave measurement.