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Abstract #4267

Optimum RF Pulse Width for Adiabatic Bloch-Siegert B1+ Mapping

Mohammad Mehdi Khalighi1, Adam B. Kerr2, Brian K. Rutt3

1Applied Science Lab, GE Healthcare, Menlo Park, CA, United States; 2Department of Electrical Engineering, Stanford University, Stanford, CA, United States; 3Department of Radiology, Stanford University, Stanford, CA, United States

The adiabatic Bloch-Siegert (B-S) method has been introduced to design short highly sensitive frequency-swept B-S pulses to address the long TE and high SAR problems of B-S B1+ mapping method; however, it is not clear which ABS pulse width gives the best results. Here we have compared ABS pulses with different pulse widths and showed that the best ABS pulse width, which generates the highest angle-to-noise ratio (ANR) is T2*. We used 2, 4 and 6ms ABS pulses in brain at 7T and showed that 6ms ABS pulse generates highest ANR maps.

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Keywords

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