Estimation of myocardial kinetic energy in gated SPECT images

Conventional methods for the analysis of left ventricle (LV) wall motion are based on 2D images with many hardly fulfilled assumptions. The methods in use today suffer from several problems as they do not take into account three-dimensional (3D) information that can be provided by image modalities such as nuclear medicine and MRI. This work describes a method to quantify 3D LV motion by a series of 3D velocity vector fields that are computed automatically for each voxel on the sequence of 16 cardiac volumes. Using the velocity it is possible to estimate the kinetic energy for each voxel. The integration of this quantity over the LV muscle gives an estimate of the left ventricle wall kinetic energy. A curve representing the myocardial kinetic energy can be plotted and used as an indicator of cardiac conditions. The proposed method was applied to the study of normal and abnormal hearts. Results have shown that the curve pattern for hearts with infarct differs substantially from a normal heart