CARDIAC LEFT-VENTRICULAR VOLUME CHANGES ASSESSMENT BY LONG AXIS ECHOCARDIOGRAPHICAL IMAGE-PROCESSING

The authors describe a new fully automatic algorithm for left ventricu lar (LV) volume change measurement and assessment from both 2-chamber and 4-chamber apical views of echocardiographic images based on the Am erican Society of Echocardiography (ASE) recommendations. The method i dentifies the left ventricular endocardium (LVE) in a 'centrebased' ap proach. In this approach the left ventricular centre point (LVCP) is f irstly approximated using a robust fuzzy based technique. The LVE edge points are then searched for on nonuniform distributed radial lines e manating from the LVCP using a multiresolution edge detection techniqu e based on the global maximum of wavelet transform (GMWT). The extract ed edge points are then spatially/temporally processed to identify the final smooth boundary using cubic-B-splines. The extracted LVEs in a complete cardiac cycle, together with the standard approximating formu la, are then used to compute the LV volume evolution in a cardiac cycl e. Experiments with real two-dimensional echocardiographic images are presented. The accuracy of the GMWT edge detection technique, which is the heart of the system, is compared to the conventional Sobel and La place edge operators.