ACTIVE CONTOUR MODELS-BASED SEGMENTATION OF LEFT VENTRICLE IN ULTRASOUND IMAGES FOR DIFFERENT AXES VIEWS.

Segmentation of the left ventricle in ultrasound images for viewing through different axes is a critical aspect. This paper proposes the development of novel active contour models with shape constraint to segment the left ventricle in three different axis views of the ultrasound images. The shapes observed in all the axis views of the left ventricle were not similar. According to the cardiac cycle, the valve opening in the end-diastolic phase influenced the left ventricle segmentation; hence, a shape constraint was embedded in the active contour model to keep ventricle's shape, especially in the Apical long-axis view and Apical four-chamber view. Furthermore, for different axes views, diverse active contour models were proposed to fit each situation. The shape constraint in each function for different views exhibited a specific shape during the function iteration. In order to speed up the algorithm evolution, previous results were used for the initialization of the present active contour. We evaluated the proposed method on 57 patients with three different views: Apical long-axis view, Apical four-chamber view and Short-axis view at the papillary muscle level and obtained the Dice similarity coefficients of 0. 8 6 ± 0. 0 5 , 0. 9 0 ± 0. 0 6 and 0. 9 0 ± 0. 0 6 and the Hausdorff distance metrics of 1 0. 1 1 ± 4. 6 6 , 7. 4 1 ± 4. 4 6 and 9. 9 8 ± 6. 5 8 , respectively. The qualitative and quantitative evaluations showed an advantage of our method in terms of segmentation accuracy. [ABSTRACT FROM AUTHOR]