Theoretical simulations of B0 distributions in the heart showed an overall average spatial correlation coefficient of 0.91 with in vivo measurements across the cardiac cycle.
Observational (n=8)
Theoretical simulations of B0 distributions in the heart were successfully validated by in vivo measurements, demonstrating oscillatory characteristics due to cardiac motion.
Effect estimate: average correlation coefficient of 0.91
Abstract Purpose Functional cardiac MRI scans employing balanced steady‐state free precession sequences suffer from dark band artifacts in the myocardium due to B 0 inhomogeneity. We recently introduced a novel method for the theoretical derivation of B 0 distributions in the human heart. This study aims to simulate the B 0 distributions in the heart across the cardiac cycle using structural MR images and validate the simulations via in vivo measured cardiac phase‐specific B 0 maps on the same subjects at 3T. Methods Cardiac phase‐specific B 0 field maps were acquired from eight healthy subjects at 3T. B 0 conditions were simulated based on tissue masks created from the cardiac‐phase specific structural images from the in vivo B 0 map scan and anatomical images from a thoracic MRI scan, adopting our recently published approach. The simulations and in vivo measurements were compared by calculating the spatial correlation of their B 0 distributions and temporal correlation of the derived spherical harmonic coefficients throughout the cardiac cycle. Results The spatial comparison of B 0 maps between the simulation and in vivo measurement indicates an overall average correlation coefficient of 0.91 across the cardiac cycle in all subjects. Both groups show consistent high‐level B 0 patterns. Temporal variations of B 0 conditions exhibit sinusoidal characteristics and are strongly correlated between simulation and in vivo. Conclusion Theoretical simulations employing regional anatomical features were validated by direct in vivo B 0 mapping in the same subjects. The spatial B 0 condition throughout the cardiac cycle exhibits oscillatory characteristics due to structural distortions of cardiac motion.
Shang et al. (Sun,) conducted a observational in Healthy subjects (n=8). Theoretical simulation of B0 distributions vs. In vivo measured cardiac phase-specific B0 maps was evaluated on Spatial correlation of B0 distributions between simulation and in vivo measurement (average correlation coefficient of 0.91). Theoretical simulations of B0 distributions in the heart showed an overall average spatial correlation coefficient of 0.91 with in vivo measurements across the cardiac cycle.