I would like to use subfield specific hippocampus maps that were produced Dr Iglesias's Lab: https://sites.google.com/site/jeiglesias/hippocampal-subfields

These maps are available via FreeSurfer, however our lab is trying to segment hippocampus subregions from already manually extracted hippocampuses. In other words, we have manually traced hippocampus masks in a NIFTI format that we would like to co-register with these maps. 

How can I directly download subfield specific hippocampal atlases in a NIFTI format so that we can use non linear co registration after?

Thank you very much.

Look forward hearing from you,

Arsenije