STrategically Acquired Gradient Echo (STAGE) imaging, part II: Correcting for RF inhomogeneities in estimating T1 and proton density

PURPOSE: To develop a method for mapping the B₁ transmit (B_1t) and B₁ receive (B_1r) fields from two gradient echo datasets each with a different flip angle and from these two images obtain accurate T₁ and proton density (PD) maps of the brain. METHODS: A strategically acquired gradient echo (STAGE) data set is collected using two flip angles each with multiple echoes. The B_1t field extraction was based on forcing cortical gray matter and white …