Figure 7From: Iterative multi-channel radio frequency pulse calibration with improving B1 field uniformity in high field MRI Flip angle maps obtained by the double angle method (DAM). The flip angle calibration for the nominal flip angle of 90 degrees has been done by the quadrature excitation (a,d), the iterative RF pulse calibration (b,e) and the conventional B1 shimming (c,f) for an axial slice (a,b,c) and a coronal slice (d,e,f).Back to article page