Accounting for through-plane motion using slice-following harmonic phase imaging revealed substantial errors in peak average rotation (up to 58% in basal slices) and torsion (19%) when ignored.
Cross-Sectional
Does slice-following harmonic phase imaging improve the accuracy of left ventricular rotation quantification compared to methods without slice-following in normal volunteers?
Accounting for through-plane motion using slice-following harmonic phase imaging is critical for accurate quantification of left ventricular rotation.
Noninvasive quantification of regional left ventricular rotation may improve understanding of cardiac function. Current methods used to quantify rotation typically acquire data on a set of prescribed short-axis slices, neglecting effects due to through-plane myocardial motion. We combine principles of slice-following tagged imaging with harmonic phase analysis methods to account for through-plane motion in regional rotation measurements. We compare rotation and torsion measurements obtained using our method to those obtained from imaging datasets acquired without slice-following. Our results in normal volunteers demonstrate differences in the general trends of average and regional rotation-time plots in midbasal slices and the rotation versus circumferential strain loops. We observe substantial errors in measured peak average rotation of the order of 58% for basal slices (due to change in the pattern of the curve), -6.6% for midventricular slices, and -8.5% for apical slices; and an average error in base-to-apex torsion of 19% when through-plane motion is not considered. This study concludes that due to an inherent base-to-apex gradient in rotation that exists in the left ventricular, accounting for through-plane motion is critical to the accuracy of left ventricular rotation quantification.
Brotman et al. (Thu,) conducted a cross-sectional in Normal volunteers. Slice-following tagged imaging with harmonic phase analysis vs. Imaging without slice-following was evaluated on Peak average rotation and base-to-apex torsion. Accounting for through-plane motion using slice-following harmonic phase imaging revealed substantial errors in peak average rotation (up to 58% in basal slices) and torsion (19%) when ignored.