3-DIMENSIONAL MYOCARDIAL DEFORMATIONS - CALCULATION WITH DISPLACEMENTFIELD FITTING TO TAGGED MR-IMAGES

PURPOSE: To reconstruct three-dimensional (3D) myocardial deformations from orthogonal sets of parallel-tagged magnetic resonance (MR) image s. MATERIALS AND METHODS: Displacement information in the direction no rmal to the undeformed tag planes was obtained at points along tag lin es. Three independent sets of one-dimensional displacement data were u sed to fit an analytical series expression to describe 3D displacement as a function of deformed position. The technique was demonstrated wi th computer-generated models of the deformed left ventricle with data from healthy human volunteers. RESULTS: Model deformations were recons tructed with a 3D tracking error of less than 0.3 mm. Error between es timated and observed one-dimensional displacements along the tags in 1 0 human subjects was 0.00 mm +/- 0.36 (mean +/- standard deviation). R obustness to noise in the tag displacement data was demonstrated by us ing a Monte Carlo simulation. CONCLUSION: The combination of rapidly a cquired parallel-tagged MR images and field-fitting analysis is a valu able tool in cardiac mechanics research and in the clinical assessment of cardiac mechanical function.