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Abstract #2771

SAR Comparison for "Head First" and "Feet First" Patient Loading at 3T MRI with Numerical Simulations

Xin Chen1, Yong Wu2, Zhen Yao2, Michael Steckner1, Robert Brown2

1MR, Toshiba Medical Research Institute USA, Inc., Mayfield Village, OH, United States; 2Department of Physics, Case Western Reserve University, Cleveland, OH

Numerical simulations of SAR have been widely used to investigate MRI RF safety. Although studies have covered multiple human models , imaging landmarks , and transmit body coil types , more clinical imaging scenarios remain to be investigated, such as patient scanned as head first or feet first. Eddy current induced in conductive imaging subject by RF magnetic field is asymmetric even with a perfectly symmetric phantom and coil. Human tissue heterogeneity and asymmetry add even more complexity to this phenomenon. In this work, we used FDTD numerical simulations to study a generic body transmit coil loaded with a digital human model. Simulations were performed for 11 imaging landmarks from head to toe, both head first and feet first. Significant differences in peak local SAR were observed for two loading directions.

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Keywords

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