Combining shape and speckle tracking for deformation analysis in echocardiography using radial basis functions

The quantification of left ventricular motion can provide valuable information about cardiac function. Echocardiography provides a non-invasive, readily available method for generating real time images of the left ventricle. Two methods for myocardial deformation tracking that have been used are shape tracking and speckle tracking. These two methods provide complementary information. Shape tracking gives high accuracy on epi- and endocardial boundaries, with speckle tracking providing good displacements across the myocardium. The methods presented here combine the results of these two methods using multilevel radial basis functions. Ultrasound data was acquired on six canines, (three baseline and three post coronary occlusion). Calculated strain values showed significant differences between the baseline and post-occlusion datasets in the occluded regions, while the remote regions did not change much. For one baseline animal, comparison to tagged MRI strain values showed reasonable agreement.