Signal to Noise Ratio Analysis of Bloch-Siegert B1 Mapping
نویسندگان
چکیده
Introduction: B1 mapping is important in a variety of new MR applications, including the design of RF pulses in parallel transmit systems and flip angle calibration for T1 mapping. The Bloch-Siegert (BS) B1 mapping method has been recently introduced as a fast, accurate and robust technique for B1 mapping [1]. In order to compare the quality of B1 maps acquired with the BS method to other methods, we derived analytical expressions for SNR in B1 maps generated by the BS, AFI [2] and "classical" long-TR double angle (DA) methods. We then compared B1 SNR between these methods, using both theoretical and experimental approaches.
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