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Abstract #4165

Characterization and Compensation of Eddy Current Induced by Insertable DreMR Magnet

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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Keywords

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