FIGURE 5.

Comparison of maternal and fetal peak local SAR (pSAR10g) and fetal average SAR (aveSAR) for different RF shim settings across various body models. Worst-case: RF shim setting that maximizes an individual SAR metric, CP mode: circularly polarized birdcage mode, improved imaging performance: both average $\left|{\text{B}}_1^{+}\right|$ and $\left|{\text{B}}_1^{+}\right|$ coefficient of variation (CV) is improved compared with CP mode, improved SAR: all three SAR metrics are less than the CP mode values of the corresponding model