Effects of phase encode order and segment interpolation methods on the quality and accuracy of myocardial tags during assessment of left ventricular contraction.

Tissue tagging can be implemented during cardiovascular magnetic resonance imaging exams to assist with the quantification of left ventriculargeometry, volume and ejection fraction, endocardial thickening and relaxation, and myocardial stress-strain relationships. During tagged cine gradient echo image acquisitions of left ventricular wall motion, rows of k-space data can be acquired with various phase-encoding orders, and the reconstruction of supplemental images can be accomplished using a variety of interpolation techniques. In this study, we investigated the utility of various phase order and segment interpolation methods for determining accurate tag displacement trajectories. Center-out phase order image acquisition with reconstruction using linear interpolation provided the highest tag position and displacement accuracy. Therefore, it is recommended that myocardial tagging exams be acquired with center-out phase encode order and reconstructed using linear segment interpolation when used for performing quantitative analysis of cardiovascular structure and function.