Qi Duan1, Souheil J. Inati2, Peter van Gelderen1, Sunil Patil3, Jeff H. Duyn1
1Advanced MRI section, LFMI, NINDS, National Institutes of Health, Bethesda, MD, United States; 2Functional MRI Facility, NIMH, National Institutes of Health, Bethesda, MD, United States; 3Center for Applied Medical Imaging, Siemens Corporation, Corporate Research, Baltimore, MD, United States
Mitigation of transmit field inhomogeneity at high field greatly benefits from subject specific B1 mapping. However, the generally long scan times of mapping techniques limit their practical use. Here, modifications to the Bloch Siegert (BS) B1 mapping method are implemented to allow whole brain B1 mapping within 40s. The effectiveness of these modifications, including an improved gradient scheme, improved BS pulse, and EPI readout, is demonstrated in phantoms and human brain.