I was wondering if it is necessary/mandatory to do distortion correction as a step in fMRI preprocessing? I got confused because I’ve seen papers both with and without this step in the preprocessing pipeline. (I am processing images acquired from a 7T scanner if that is relevant.)
In addition, after looking into the guides I found that I might be missing the field map / reverse phase encoding image that is needed for SDC, so I was also wondering if there is any remedy to this if the step is necessary.
Thank you very much for your help in advance!