Assessing LV wall motion by frame-to-frame curvature matching and optical flow estimation

This work seeks to describe left ventricle (LV) shape by optimizing the curvature computation. A method based on adaptive Fourier series approximation was developed and compared with three known methods. The authors also wish to assess wall motion by applying both the optical flow method and an improved shape matching algorithm, as well as to compare their results with each other and with the centerline method. First, the points of curvature extrema along each contour are tracked frame-to-frame, extrapolated if necessary throughout systole and selected by restrictive criteria. Second, the points lying among these markers are mapped onto the next contours proportionally to local displacement and curvature changes. Results are in closer agreement with physiology knowledge than those of both the centerline and optical flow methods