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Abstract #4420

Online Local SAR Supervision for Transmit Arrays at 7T

Rene Gumbrecht1, 2, Ulrich Fontius1, Holger Adolf1, Thomas Benner1, Franz Schmitt1, Elfar Adalsteinsson3, 4, Lawrence L. Wald, 45, Hans-Peter Fautz1

1Siemens Healthcare, Erlangen, Germany; 2Department of Physics, University of Erlangen, Erlangen, Germany; 3Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States; 4Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States; 5Department of Radiology, A. A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States

Local SAR and its safe supervision are dominant limiting factors for high performance pTX applications. Safety concepts typically provide a SAR prediction strategy based on numerical simulations. Only sequences that will not exceed SAR limits are allowed to be executed. To capture system fault during runtime, an additional online supervision was proposed to ensure the correct execution of the RF pulses. In this study, an online local SAR calculation and supervision system using measured RF pulse shapes was built. Local SAR is calculated in near real-time based on a compressed electric field model of the current coil and patient.

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Keywords

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