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Regional cardiac function analysis from tagged MRI images. Comparison of techniques: Harmonic-Phase (HARP) versus Sinusoidal-Modeling (SinMod) analysis. Magn Reson Imaging 2018 12;54:271-282



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Scopus ID

2-s2.0-85053456499   5 Citations


Cardiac MRI tagging is a valuable technique for evaluating regional heart function. Currently, there are a number of different techniques for analyzing the tagged images. Specifically, k-space-based analysis techniques showed to be much faster than image-based techniques, where harmonic-phase (HARP) and sine-wave modeling (SinMod) stand as two famous techniques of the former group, which are frequently used in clinical studies. In this study, we compared HARP and SinMod and studied inter-observer variability between the two techniques for evaluating myocardial strain and apical-to-base torsion in numerical phantom, nine healthy controls, and thirty diabetic patients. Based on the ground-truth numerical phantom measurements (straina??=a??-20% and rotation anglea??=a??-4.4A?), HARP and SinMod resulted in overestimation (in absolute value terms) of strain by 1% and 5% (strain values), and of rotation angle by 0.4A? and 2.0A?, respectively. For the in-vivo results, global strain and torsion ranges were -10.6% to -35.3% and 1.8A?/cmA to 12.7A?/cm in patients, and -17.8% to -32.7% and 1.8A?/cm to 12.3A?/cm in volunteers. On average, SinMod overestimated strain measurements by 5.7% and 5.9% (strain values) in the patients and volunteers, respectively, compared to HARP, and overestimated torsion measurements by 2.9A?/cm and 2.5A?/cm in the patients and volunteers, respectively, compared to HARP. Location-wise, the ranges for basal, mid-ventricular, and apical strain in patients (volunteers) were -8.4% to -31.5% (-11.6% to -33.3%), -6.3% to -37.2% (-17.8% to -33.3%), and -5.2% to -38.4% (-20.0% to -33.2%), respectively. SinMod overestimated strain in the basal, mid-ventricular, and apical slices by 4.7% (5.7%), 5.9% (5.5%), and 8.9% (6.8%), respectively, compared to HARP in the patients (volunteers). Nevertheless, there existed good correlation between the HARP and SinMod measurements. Finally, there were no significant strain or torsion measurement differences between patients and volunteers. There existed good inter-observer agreement, as all measurement differences lied within the Bland-Altmana??A?a??2 standard-deviation (SD) difference limits. In conclusion, despite the consistency of the results by either HARP or SinMod and acceptable agreement of the generated strain and torsion patterns by both techniques, SinMod systematically overestimated the measurements compared to HARP. Under current operating conditions, the measurements from HARP and SinMod cannot be used interchangeably.

Author List

Ibrahim EH, Stojanovska J, Hassanein A, Duvernoy C, Croisille P, Pop-Busui R, Swanson SD


El-Sayed H. Ibrahim PhD Associate Professor in the Radiology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Diabetes Mellitus, Type 1
Heart Ventricles
Image Processing, Computer-Assisted
Magnetic Resonance Imaging
Myocardial Contraction
Observer Variation
Phantoms, Imaging
Reproducibility of Results
Young Adult