Merging .mif files

1

Very new to mrtrix, but with previous experience in FSL. I’m planning to run an fixel based analysis and I’m going to start from scratch with the dicoms. We have a few DTI images for each patient from the same day, and the usual practice is to merge them with fslmerge -t. I was wondering how to do the same with .mif files. Can I still use fslmerge? Is there a different way to merge in time in mrtrix?

Thanks!

2

You could, but we would recommend dwicat instead. :wink:

3

thanks! Is there an option to specify what dimension the images are merged in? Or does it do time automatically?

4

All our tools assume the data need to be concatenated along the 4th axis, so that’s what this tool does. I think that’s the axis that corresponds to time in the NIfTI standard, but I can’t quite remember – we don’t tend to force any particular interpretation on what dimension means what in MRtrix…

5

If you were to be using the mrcat command, then the axis for concatenation follows the logic as outlined in the relevant command-line option. However the dwicat script explicitly assumes that you are combining DWI volumes acquired across separate sessions, and therefore concatenation always occurs along axis 3 (which is the fourth axis).