Description of a new strain and displacement estimator for elastography

A new estimator, which estimates directly strain as scaling factor or time delay is presented. The algorithm is based on the zero seeking of cross-correlation imaginary part. This term can be calculated using only real RF signals. Estimator performances are evaluated on simulated noisy images and show that strain estimation is correct up to 10% strain, and delay estimation is correct up to the half central period with a good accuracy for the small delays, 0.01 × Ts (sampling period).