Selecting specific volumes when using dti_fit

Hello everyone.

I have a data set consisting of b=0, b=1000 and b=2500 dwi images. However, when calculating tensors with dti_fit, I want to use only b=0 and b=1000 images and not b=2500 images. b=1000 images are in the first 64 volumes. How can I do this?

Hi @baris_genc ,

You might find the dwiextract MRtrix3 command helpful, something like:

dwiextract dwi_orig.nii.gz dwi_1000.nii.gz -bzero -singleshell \
-shells 0,1000 -fslgrad bvec_orig bval_orig \
-export_grad_fsl bvec_1000 bval_1000

You could use a full MRtrix3 workflow to get your tensor metrics by using dwi_1000.nii.gz bvec_1000 bval_1000 in commands dwi2tensor and tensor2metric.


Thank you for your help Steven.