• Corpus ID: 45057400

Transmit B 1 Shimming at High Field with SAR Constraints : A Two Stage Optimization Method Independent of The Initial Set of RF Phases and Amplitudes

  title={Transmit B 1 Shimming at High Field with SAR Constraints : A Two Stage Optimization Method Independent of The Initial Set of RF Phases and Amplitudes},
  author={T-H. Chang and Z.-Q. Luo and X. Wu and Can E. Akgun and Tommy Vaughan and K{\^a}mil Uğurbil and P-F. van de Moortele},
Introduction: There has been an increasing interest in constraining transmit B1 shimming with specific absorption rate (SAR) limits [1-2], especially at high magnetic field. Since most of the existing methods rely on solving a nonconvex optimization problem, they are typically faced with two difficulties: Only local optimum solutions are obtained, and they are susceptible to the chosen initial points for optimization. Here we introduce a two stage optimization method where a reliable initial… 
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