Motion and deformation of the left ventricular wall may be quantified by following the motion of markers as a function of time. The 3-D trajectories of the markers can be reconstructed when time sequences of frames in two projections are available. Distance between subregions is 7 mm.
Solid lines correspond to raw data, dotted lines to filtered data.
So that the different tracings may be distinguished, they have been shifted vertically. Vertical lines denote begin- ning and end of ejection phase based on recording of aortic volume flow. The set of tracks corresponding with M markers observed in a sequence of T frames is represented by a 2M x T matrix of marker coordinates as a function of time. An efficient method to reduce the noise in marker tracks has been developed by utilizing the coherence of motion in a set of markers. The method has been valuated in a computer simulation and in a physiological experiment.