I have a Diffusion MRI dataset and each subject has 64 gradient directions and one b0. I downloaded them from PPMI. I want to implement Eddy Current preprocessing for motion and distortion correction, but it requires opposite phase-encoded b0 images. I don’t know how to get opposite phase-encoded images of my dataset and implement Eddy Current. I would be grateful if anyone had experience in Eddy Current and help me.
Reverse phase-encoded images need to be acquired as part of the imaging protocol. If you don’t have them in your dataset you’ll have to perform the distortion correction using a different method. It looks like PPMI suggest a registration based method for distortion correction, see the links below:
Thanks a lot for your useful discription.