Cross correlation for aligning 3D ultrasound derived endocardial surface

Two 2-D polar coordinate tables are used to describe the 3-D endocardial surface of the left ventricle at the end of both systole and diastole. A truncated ellipsoid is used as a preliminary model of the left ventricle. Cross correlating two truncated ellipsoids of different degrees of rotation around the origin of the reference system results in a definitive measure of the rotational difference between the two surfaces. Cross correlation is used to derive such information from the real cardiac endocardial surface data derived from 3-D transoesophageal ultrasound images