Analysis Of The Common Atrioventricular Ring In 3D Echocardiography

The quantitative measurement and analysis of static and dynamic state of common atrioventricular annulus and common atrioventricular valve leaflet are important to the diagnosis and therapy of some heart disease. Thanks to the three dimensional echocardiography, it can indicate the complex inside structure of heart. Cooperating with Shanghai children medical center, we present the work of measurement and analysis of common atrioventricular valve, especially the common atrioventricular annulus by three dimensional echocardiographs in this thesis.The innovation of this thesis is as following:1). According to actual characteristic of common atrioventricular valve, complex common atrioventricular valve 3D motion was decomposed into global motion and regional motion. Companied with the motion of heart due to the aspiration, common atrioventricular valve has global motion throughout the cardiac cycle. Based on the three dimensional echocardiography, a reference plane of common atrioventricular annulus was proposed to eliminate the global motion, and provide a reference plane for measurement the static and dynamic parameters of the common atrioventricular annulus. Experimental results show that our approach can provide a more reliable measure of the common atrioventricular annulus dynamic behavior.2) We try to obtain more information about mitral valve and common atrioventricular valve before and after surgery and then discuss about the value of it in atrioventricular septal defects surgical treatment by making use of manual and automatic methods combined with up-to-date 3D real-time echocardiography and unconnected computer assistance. The experiment indicates that three correlationships exist between proportion of parts of anterior and posterior bridging leaflet in mitral valve before surgery and total area of mitral valve and rate of refluxing variation, proportion of area of mitral ring after surgery and area of common atrioventricular ring and rate of mitral refluxing variation after surgery, and proportion of area of left bridging leaflet and total mitral area and rate of mitral refluxing improvement after surgery.3) Based on real-time three-dimensional echocardiography images, a dynamic analysis method describing atrioventricular annulus represented by connected curve angle chain is suggested. The traditional methods of describing theatrioventricular valve are composed of the perimeter, the orifice area and the area of atrioventricular annulus. We have proved that the proposed connected curve angle chain is invariant to rotation, scaling, and translation. Experimental results show that the proposed approach can be feasibly used for describing the atrioventricular valve, and can quickly get motion of atrioventricular annulus throughout the cardiac cycle.4) We have developed a package of computer-aided visualization of 3D echocardiography image and quantitative measurements of common atrioventricular annulus and common atrioventricular valve leaflet. At the beginning, the boundary points on the common atrioventricular annulus are marked by doctors interactively. Since these marked points are not distributed uniformly and sequentially, it is necessary in the second step to re-arrange these points into a set of sequences of points on a contour of the common atrioventricular annulus. Thirdly, in order to assess the geometry of the 3D common atrioventricular annulus, it is modeled by a 3D non-uniform rational B-spline (NURBS). At last, the parameters related to the dynamics of the common atrioventricular annulus throughout the cardiac cycle are calculated in a 3D Cartesian coordinate system.