Extraction Of Left Ventricular Wall Mechanical Indexes Using Four-Dimensional Image Analysis Of Mri, Based On A Nonlinear Hyperelastic Model

Abstract

Purpose:<br /> Cardiac diseases is and will be a leading cause of death in the world. Locating and measuring extent of infarct region by local parameters can used as a computer aided diagnostic tool in cardiac imaging centers.<br /> Methods:<br /> First CMRI data processed blindly by cardiologist to score cardiac wall kinesis. In the following using segmented Cine CMR images, 3D meshed template of LV wall constructed, then by robust weighted normalized mutual information algorithm the sparse points were tracked. Finally, by fitting 3D nonlinear active mesh model to the sparse point displacements, dense motion field was estimated and then local parameters of left ventricle in healthy individuals and infarct patients were calculated. Local parameters include; path length, fractional thickening and strain.<br /> Results:<br /> Local parameters of Left ventricle in 30 individuals were calculated by hyperelastic based active mesh model. Results showed more than 50% reduction in local parameters amplitude in infarct regions. Validation of proposed method has been done by obtained error between estimated point by model and analytical point of synthetic images. Results showed mean RMSE= 0.15 mm for synthetic data and RMSE= 0.17 mm for real data. Fractional wall thickening results revealed more than 20% reduction in infarct regions. Comparison of path-lengths with cardiologist scoring of cardiac wall kinesis showed 78% accuracy.<br /> Conclusions:<br /> Proposed method determined the affected region in all patients. Given the promising results of the proposed method Based on the promising results, the proposed method can be used as a diagnostic aid tool in imaging centers.