Cardiac functional magnetic resonance imaging at 7T: Image quality optimization and ultra-high field capabilities

Figure 2 Estimation of the B1 transmission field in a volunteer scan. A: Gradient-echo short-axis image; B: B1 scale factor map (range, 0 to 1); C: Proton density distribution map (arbitrary units; a.u.); D: R² fitting map (range, 0 to 1) shows excellent simulation fittings; E: Example of signal intensity measurements (arbitrary units; a.u.) at different flip angles in degrees (dots) and the fitting curve inside the heart region (red circle). The results show altered B1 field across the imaged slice. FA: Flip angle.