Validation of optical-flow for quantification of myocardial deformations on simulated RT3D ultrasound

Quantitative analysis of cardiac motion is of great clinical interest in assessing ventricular function. Real-time 3-D (RT3D) ultrasound transducers provide valuable four-dimensional information, from which quantitative measures of cardiac function can be extracted. Previously, we presented a method based on four-dimensional optical flow motion estimation for anatomical tracking of myocardium in RT3D ultrasound, from which myocardial displacement fields and dynamic cardiac metrics were computed. In this paper, in order to quantitatively validate our method, we build a truly 3D mathematical phantom of cardiac tissue and blood. Distinguished from previous studies, our work further decomposes tissue impedance into cell kernels and processes all functions in 3D. Instead of simply modeling the myocardium, a "quasi-LV" phantom is built including myocardium and blood. Also all ultrasound probe parameters used in this work are directly estimated from clinical RT3D data instead of using common parameters from 2D transducers. Based on this phantom, simulated RT3D ultrasound data sets are generated for validation to assess the performance of an optical flow based method in tracking myocardial tissues.