Design and SAR Estimation of a Segmented Loop for Dual Coil CASL at 9.4 T

Jonas Bause¹, G. Shajan¹, Jens Hoffmann¹, Klaus Scheffler¹, Rolf Pohmann¹

Dual-Coil Continuous Arterial Spin Labeling (DC-CASL) can reduce magnetization transfer and increase SNR. Here a balanced detunable segmented loop coil for DC-CASL in humans at 9.4T was developed and FDTD simulations were performed to estimate the optimal phase shift as well as the local SAR. The simulations showed that sufficient labeling is possible without exceeding the IEC limits when the duty cycle is limited to 25 %. An additional safety margin of 37 % was included in the SAR calculations to account for deviations in the position of the coils.