Simulation of Focused RF Heating using a High-Channel-Count RF Array and a Maximum SAR Algorithm 

A 70-channel parallel transmit RF coil array intended for focused RF applications was designed and simulated at four frequencies (298 MHz, 447 MHz, 900 MHz and 1200 MHz) using a Ella body model. A previously proposed maxSAR algorithm was used to focus SAR in target regions while limiting the SAR in background tissues. Spatial maps of optimized SAR distribution are shown for several target locations and all frequencies. SAR distributions together with temperature and CEM43 maps suggest that clinical levels of focused hyperthermia can be achieved using high channel count parallel transmit RF coils and the maxSAR algorithm.