I have a nifti file of dimension (256, 256, 156) but once I run the freesurfer recon-all the subregions mask "aparc.DKTatlas+aseg.mgz" has a dimension of (256,256,256) due to this I am unable to view the segmentation overlaid on the original image in any dicom viewer.

May I know why freesurfer changes the dimension of the original image and the mask ?

Is there any solution for this?

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