Non-tracking-based 2D strain estimation in tagged MRI

Tagged MRI is a non-invasive technique to assess myocardial deformations. In this paper, we developed a novel non-tracking-based strain estimation method for tagged MRI. This method is based on the extraction of tag´s deformation gradient, and therefore avoids the limitations of conventional tracking-based strain estimators. We tested this method on both simulated and real world images. In simulated images, we quantitatively evaluated the accuracy and robustness of our non-tracking estimator. We find that the results of circumferential strain and local tissue rotation angle are highly consistent with the ground truth values. We also tested our method on both normal and patient data. Real world tests show our results are valuable to visually distinguishing normal and abnormal data, and have the potential to quantitatively diagnose cardiac malfunctions or diseases.