Ultrasound-based strain rate estimation of moving, fully-developed speckle

Strain rate is a measurement that may aid a cardiologist in assessing myocardial function. Ultrasound Doppler techniques can be used to compute tissue velocity relative to a transducer, and the myocardial strain rate is the localized spatial derivative of the tissue velocity. Such a strain rate estimate is typically numerically noisy. We derive the relevant speckle statistics to faciliate the use of a weighted least squares regression to estimate the strain rate, showing that a statistically appropriate weighting is the product of the ultrasound signal amplitudes