Question

Question Posted 10/13/16:
I am wondering, is the PET data standardized, or regularized so that the pixel corresponding to the same voxel for all patients?
I tried to download some patients data with label
'PIB Coreg, Avg, Standardized Image and Voxel Size'.
But some images seems to have smaller circumference for the same slice (same z axis). I am wondering is there PET images which have been standardized for voxels. And if there is, how can I search for those in the search engine of the LONI data base. Thanks
Response posted 10/13/16 by Robert Koeppe:
The four sets of "pre-processed" PET images, including the two sets that say Standardized image and voxel size, are NOT non-linearly warped so the answer is no. Only the grid is the same. These all have 160x160x96 image grides with 1.5mm3 voxels. My group is responsible for uploading these four sets of "pre-process" iamges, like the one you mention.
Other processed images have been non-linearly warped, but someone else will need to answer how to get those.
Response posted 10/13/16 by Susan Landau:
Most of the PET images are not available in a spatially normalized format. Only a subset of the FDG PET images have been spatially normalized and made available for download. To find those, Advanced Images Search --> Image Types --> Post Processed (check) --> Image Modality --> PET (check) --> Image Series Description --> *Spatially Normalized*
Response posted 10/31/16 by Ying Liu:
Thanks for the clarification.

I have a question. For these spatially normalized images, what Radiopharmaceutical is used?

Is it F-florbetapir? Are they using the same radiopharmaceutical?

I tried to let the search result list the radiopharmaceutical by checking the box, but it doesnot list it in the results. And when I check all the radiopharmaceutical boxes, no search result is given.

I read that change in amyloid difference in the white and gray matter is a good classifier for AD and MCI. I wonder does all radiopharmarceuticals indicate the amyloid value? I want to compare among spatially normalized PET images with same radiopharmarceutical to make some claims about the patterns regarding amyloid for patients with different features.

Thanks,
Ying