Fig1.

STIMS pulse sequence diagram for 2-fold echo-shift acceleration. The first MultiBand pulse excites odd slices, and the readout is shifted to the second TR. The second RF excites the even slices, with signal readout at the third TR. This allows effective TE to be long, thereby providing increased phase and T₂* contrast. STIMS allows half of the imaging volume to be excited simultaneously, which provides the SNR benefit of volumetric signal averaging. Because the slice thickness that needs to be resolved is doubled for each slice group, the number of kz phase encodes is reduced by half, providing 2-fold acceleration.