Figure 37

bSSFP and B0 inhomogeneities. a) bSSFP steady-state signal as a function of frequency-offsets (RF flip angle 50 degrees, TR 2.2 ms). The signal is approximately constant except at multiples of ≈±227 Hz where the signal drops down to near zero, forming dark bands in these regions. b) Spherical phantom imaged with a bSFFP sequence with an homogenous B0. c) Phantom image repeated with a field gradient from left to right. Dark bands are formed where the frequency offsets are multiples of ≈±227 Hz. d) Similar to c but with a TR twice as large, halving the distance between dark bands as a result.