Ludovic de Rochefort1, Eddy S.M. Lee2, Matteo Polello3, Luc Darrasse1, Gianni Ferrante3, Brian K. Rutt2
1UMR8081, IR4M (Imagerie par Rsonance Magntique Mdicale et Multi-modalits), Univ. Paris-Sud, CNRS, Orsay, France; 2Radiology, Stanford University, Stanford, CA, United States; 3Stelar s.r.l, Mede, Italy
Delta relaxation-enhanced magnetic resonance (dreMR) imaging is a B0-cycled technology producing contrast from intended targets only. While B can be achieved with an insertable field-cycling magnet, mutual coupling induces eddy currents (EC) that change the main field. An imaging strategy is presented to characterize and compensate for the EC. A multiphase imaging sequence was modified to produce multiple images after a dreMR pulse. Results show that offset caused by EC is spatially homogeneous, proportional to B and decays monoexponentially. Consequently, the EC induced spatial shifts in the frequency encoding direction which could be compensated for using sequence adaptation and post-processing.
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