[Freesurfer] TRACULA mask error

Dear All,

I have run all of the pre-processing steps on my DTI data and as I am checking my nodif_brain_mask I have realised that some of the masks have become distorted and twisted in some way. I have attached screenshots of both the raw data (which looks fine) and the white mask (which is distorted). In addition, as I have read that it is important to check the dtifit_V1 and dtifit_FA I have also included these in the word document, incase this helps.

This distortion has occured for approximately a quarter of the subjects that I have processed and the rest look good. Please can you let me know if you have any ideas about what has gone wrong and how to fix this?

Thanks in advance for your help,

Amanda