On the Estimation of Transmural Myocardial Shear by Means of MRI Tagging

摘要

The reliability of non-invasive myocardial shear measurements based on MRI tagging is evaluated in relation to the influence of possible edge effects close to myocardial borders. Automatic cardiac motion tracking is performed with SinMod, a method based on sinusoidal wave modeling. Shear results are evaluated for simulated images with a known imposed motion field, as well as for real short-axis acquisitions from 10 healthy volunteers. To evaluate accuracy and precision in vivo, automatic results are compared with manual tracings. Results show that estimation of circumferential-radial shear is feasible in vivo, where edge effects close to myocardial borders play a minor role as compared with those found in synthetic images. In healthy subjects, circumferential-radial shear and rotation of the myocardium appear negatively correlated.