Purpose: To track three-dimensional (3D) myocardial tissue motion using slice followed cine displacement encoded imaging with stimulated echoes (DENSE).
Materials and methods: Slice following (SF) has previously been developed for 2D myocardial tagging to compensate for the effect of through-plane motion on 2D tissue tracking. By incorporating SF into a cine DENSE sequence, and applying displacement encoding in three orthogonal directions, we demonstrate the ability to track discrete elements of a slice of myocardium in 3D as the heart moves through the cardiac cycle. The SF cine DENSE tracking algorithm was validated on a moving phantom, and the effects of through-plane motion on 2D cardiac strain were investigated in six healthy subjects.
Results: A through-plane tracking accuracy of 0.46 +/- 0.32 mm was measured for a typical range of myocardial motion using a rotating phantom. In vivo 3D measurements of cardiac motion were consistent with prior myocardial tagging results. Through-plane rotation in a mid-ventricularshort-axis view was shown to decrease the magnitude of the 2D end-systolic circumferential strain by 3.91 +/- 0.43% and increase the corresponding radial strain by 6.01 +/- 1.07%.
Conclusion: Slice followed cine DENSE provides an accurate method for 3D tissue tracking.
(c) 2008 Wiley-Liss, Inc.