Use of matched filters for extraction of left ventricular features in two-dimensional short-axis echocardiographic images

摘要

Abstract: An automatic method for identification of the center point of the left ventricle of the myocardium during systole is described for 2-dimensional short-axis echocardiographic images. This method, based on the use of large matched filters, identifies a single fixed center point during systole, by locating the three features: the epicardial boundary along the posterior wall, the epicardial boundary along the anterior wall, and the endocardial boundary along the anterior wall. Thus, it provides a first step toward the long term goal of automatic recognition of the endocardial and epicardial boundaries. An index associated with the filter used to approximate the epicardial boundary along the posterior wall provides an indication of the quality of the image and a reliability measurement of the estimate. When tested on 207 image sequences, 18 images were identified by this index (applied to the end diastolic frame) as unsuitable for processing. In the remaining 189 image sequences, 16 of the automatically defined center points were judged poor when compared with estimates made on the end diastolic frame by an independent expert observer. !8