Hi,

Thanks for your instant reply! I have noticed that the DKE applied  co-registration between the diffusion weighted images for a single subject. But in general, the gradient direction of each DWI volume will also be rotated according to the transformations in the co-registration to guarantee the precious result. I want to know if these problem really matters in the DKI processing?
By the way, I found it is troublesome to identify the correct odf orientation. Is there any efficient way to work this out rather than to try all the possible orientation combinations?

Best regards and many thanks again!