Dear FSL Experts,
I'm preproc-ing dMRI data. The dataset consists of AP and PA scans. My understanding is that to correct for susceptibility and induced distortions, I will need to run:
1. topup with both AP and PA scans
2. eddy with topup results
Some suggested pipelines (i.e. the HCP) use eddy_combine after the above steps but I find little to no detailed description on what is its role. My guess is it just corrects (balances) the intensity between AP and PA scans but does not alter any structural details. Does it just simply average the corrected AP and PA scans or fit a sophisticated model instead? And it is necessary to include it in the pipeline or it is deprecated?
Any suggestion would be much appreciated.