An interactive thresholding scheme to extract myocardium from a sequence of two dimensional echocardiograms

The authors describe an interactive thresholding scheme to extract myocardium from a sequence of two dimensional echocardiograms (2DEs). An expert operator interactively picks a few points that are on the myocardium as the object points, and a few background points. The computer classifies the rest of the points of the image as myocardium or the background by comparing the echodensity at each point to a threshold which is computed as a function of the input points and their neighborhood echodensities. All the points with echodensities greater than the corresponding threshold form the myocardium and the rest form the background. This classification can be refined further by picking new sets of points at the misclassified regions