Figure 1.

(a) Schematic diagram of the triple-refocusing sequence used is shown with slice selective gradients (brown) and spoiling gradients (green) (strength 32 mT/m, length 1.7 ms, total slope length 0.8 ms). The durations of the slice selective RF pulses were kept the same in numerical simulations and experiments. The duration of the non-slice selective, second 180° RF pulse (NS180) was varied in the simulations.