• Rudolf Fritz Fischer, Christoph Barmet, Markus Rudin, Peter Boesiger, Klaas Paul Pruessmann, and Sebastian Kozerke.
• Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland.
• Magn Reson Med. 2013 Dec 1; 70 (6): 1567-79.

PurposeTo analyze and correct for eddy current-induced phase imperfections in cardiac cine balanced steady-state free precession (bSSFP) imaging.MethodsEddy current-induced phase offsets were measured for different phase-encoding schemes using a higher order dynamic field camera. Based on these measurements, offset phases were corrected for in postprocessing and by run-time phase compensation applying radiofrequency phase increments and additional compensatory gradient areas. The findings were validated using numerical simulations, phantom experiments, and in vivo cardiac scans.ResultsDepending on the phase-encoding scheme, significant eddy current-induced phase offsets were detected. Time-varying phase offsets were observed at subsequent excitations leading to steady-state distortions and hence to profile-dependent amplitude modulations in k-space. Taking into account measured k-space trajectories algebraic image reconstruction allowed compensating imperfect spatial encoding. Correction of amplitude modulations was successfully accomplished by run-time phase compensation.ConclusionUsing magnetic field monitoring, artifacts in cine balanced steady-state free precession caused by uncompensated eddy current fields can be significantly reduced.Copyright © 2012 Wiley Periodicals, Inc.

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