Simultaneous T1 and B1 Mapping Using Variable Flip Angle Imaging on Fatty Tissue

KyungHyun Sung¹, Manoj Saranathan², Bruce L. Daniel², Brian Andrew Hargreaves²

Variable flip angle (VFA) imaging is a common choice to measure T1 since it can provide fast volumetric T1 mapping, but is highly sensitive to flip angle variation. We describe a novel way to simultaneously measure T1 and B1 maps using fat-only VFA images, assuming the T1 relaxation times in fat to be globally uniform, and the B1 inhomogeneity is smoothly varying across the object. We showed B1 maps using the proposed method are similar those using the conventional double angle method. Additionally, we demonstrated we can reduce a T1 estimation error by using our simultaneous T1 and B1 mapping method.