Fig. 3.

Modulation transfer function (MTF) simulation results comparing k-t PCA and k-t SPARSE-SENSE. MTFs for undersampling factors 2, 5 and 10 are shown in the three rows. a,b MTF maps using the MRXCAT numerical phantom plotted along k _y-f at k _z = 0 (a), and along k _z -f at k _y = 0 (b). c MTF k _y -f maps derived from fully sampled 2D in-vivo data with retrospective undersampling. MTF maps were masked using an empirically determined threshold in the signal-to-artefact maps. Thresholds were set to 3 for 3D MRXCAT, and 2.5 for 2D in-vivo simulations