Gannet spectrum results

Hi all, I’m looking at some MEGA-PRESS data from the right thalamus analyzed in Gannet 3.1. The data from motor cortex and occipital cortex looks fine, but the thalamus data turned out like this. The only difference aside from voxel position was using the FASTMAP shimming routine. Could that cause spectra like this, or is this something else?

Hi @ChrisHorton,

Your data are corrupted by ghosting artifacts (spurious echoes that come from outside the voxel; please refer to Figure 14 of this paper).

Unfortunately, these artifacts are not easy to rectify during data processing; they need to be addressed at acquisition. If you are seeing this in other datasets, you can try changing the order of the slice-selective gradients.