Illustration of inter-frame 2D contour topology changes in reconstructed 4D heart model.

<p>A sequence of images (left to right, top to bottom) depicting the modeling of 2D contour topological deformation. A red plane is added as a reference, to illustrate the change in the number of contours over that plane throughout the cardiac cycle. The contours (the intersection between the red reference plane and the heart model) are observed to merge and split again.