Figure 2.

Experimentally determined PSFs for different k‐space sampling approaches for slice‐selective 2D–MRSI with a 14 × 14 matrix using a point source (i.e. inorganic phosphate solution) depicted as 2D maps (A‐C) and 1D plots (D‐F): A,D, full phase‐encoded k‐space sampling; B,E, elliptically phase‐encoded k‐space sampling; C,F, constant‐density spiral sampling with no spatial, but five temporal, interleaves. Constant‐density spirals featured a reduced number of side‐lobes in comparison with full phase encoding acquisition and provided smaller PSF than the elliptical encoding alternative (3.5 cm² versus 4.9 cm²). All signal intensities are cut at 50% of the maximum signal intensity in the 2D maps to emphasize the FWHM. Note that all maps and plots are given in absolute values, i.e. all side‐lobes are depicted as positive