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Abstract #2215

PTx Pulse Design with Explicit Hard Constraints on Local and Global SAR and Maximum and Average Forward Power

Bastien Guerin1, Matthias Gebhardt2, Elfar Adalsteinsson3, 4, Lawrence L. Wald1, 4

1Martinos Center for Biomedical Imaging, Dept. of Radiology, Massachusetts General Hospital, Charlestown, MA, United States; 2Siemens Healthcare, Erlangen, Germany; 3Dept of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States; 4Harvard-MIT Division of Health Sciences Technology, Cambridge, MA, United States

Electromagnetic simulations have shown that pTx pulse design with average forward power regularization does not constrain local SAR. We propose two pulse design interior point algorithms that explicitly constrain spatial fidelity, local and global SAR, average and maximum forward power. The first (second) minimizes excitation error (local SAR) while constraining local SAR (excitation error), global SAR and maximum/average power. We show the equivalence of these two approaches and their capability in handling large numbers of constraints without the need of defining a tradeoff parameter, giving more flexibility to the operator to explore the pulse design parameter space in real time.

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Keywords

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