A new approach to study cardiac motion: the optical flow of cine MR images.

We present a novel approach to study the intricate motion of the heart using the optical flow technique applied to cine MR images. The method uses image brightness variations between consecutive frames to compute in-plane displacements or velocities of moving image features. The dense velocity field thereby obtained throughout the myocardial wall allows to not only characterize segmental left ventricular wall motion but also to resolve "fine" motion such as intramural differences in displacements and therefore in thickening. Other subtle features of systole like the descent of the base towards the apex or the counterclockwise rotation of the apex with respect to the base can also be detected by the algorithm. Contrary to other techniques proposed earlier, this noninvasive method presents the additional advantages of not requiring any special pulse sequence nor well defined endocardial and epicardial outlines.