MRF-based channel-wise absolute B1+ mapping at low RF power in the human abdomen at 7T

For pTx applications, knowledge of the underlying Tx channel-wise B1+ profile is essential. In this work, we present a hybrid absolute B1+-mapping approach where MRF-based B1+-mapping is utilized to map the channel-wise absolute B1+ profile, providing higher accuracy at low flip angles than standard methods. The hybrid approach is compared to mapping each Tx channel separately using the MRF-based method. Phantom and body in-vivo measurements at 7T show good agreement between the two approaches.