SAR Consequences of Optimization Strategy for a 7T RF Transmit Loop Array in CP Mode

Mikhail Kozlov¹, Robert Turner¹

We numerically investigated SAR consequences of optimization strategy for a 7T RF transmit loop array in CP mode. If the non-conservative RF electric field is generally dominant, even a significant variation of the arrays current distribution due to changes in array geometry and different tuning/matching/decoupling has a very weak influence on the ratio mean B1+ over the entire human brain to square root of maximum of 10 gram average SAR , although the SAR profile varies. As a result, the same MRI RF pulse sequence may produce nearly the same SAR10g for different loop arrays, as long as similar B1+ maps are generated.