Laura Sacolick1, Seung-Kyun Lee2,
William A. Grissom3, Mika W. Vogel1
1GE Global Research,
Munich, Germany; 2GE Global Research, Niskayuna, NY, United
States; 3GE Global Research, Munich,, Germany
A fast spin echo based Bloch-Siegert B1 mapping is presented here for rapid B1 field mapping. In cases where T2* causes significant signal loss in long-echo time gradient echo images, spin echo based B1 mapping is desired. The fast spin echo uses only two off-resonance RF pulses per echo-train, resulting in lower SAR and significant B1 map acceleration. The static Bloch-Siegert phase shift causes signal loss from the non-CPMG condition, but one can reconstruct a B1 map with high SNR even for phase shifts >90 degrees with a CPMG sequence. The B1 mapping shown here is applied for both parallel and single transmit systems.
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