Question Posted 02/28/18:
We recently downloaded a batch of ADNI 3 preprocessed MPRAGE images. I noticed that a couple subjects scanned on the Siemens Verio had two images on the IDA, one with MT1;N3m and another image with MT1;N3m;GradWarp processing. The image with the gradwarp processing has a "MPRAGE_ND" in the description. Is there some reason that the Verio scans require the gradwarp? Is the 3D gradient warping correction not applied by this particular scanner? If we wish to use the 3d gradient warp corrected scan should we use the MPRAGE_ND scan? Thank you very much
Response posted 03/01/18 by ADNI MRI:
Thanks for your question to the ADNI MRI Core.

The Siemens Verio system provide distortion corrected and Non distortion corrected (MPRAGE_ND). We would recommend that you only use the standard scan and not use the “ND” unless you want non grad warp corrected scans.