• Select the area you would like to search.
  • ACTIVE INVESTIGATIONS Search for current projects using the investigator's name, institution, or keywords.
  • EXPERTS KNOWLEDGE BASE Enter keywords to search a list of questions and answers received and processed by the ADNI team.
  • ADNI PDFS Search any ADNI publication pdf by author, keyword, or PMID. Use an asterisk only to view all pdfs.


Question Posted 09/03/20:
Hope you are well. I would like to test FreeSurfer's partial volume correction tool on the ADNI3 PET data (AV45,AV1451, FBB). The tool requires a '--psf FWHM' input described as "the full-width/half-max of the the point-spread function (PSF) of the scanner as measured in image space (also known as the burring function). The blurring function depends on the scanner and reconstruction method; here it is modeled as an isotropic Gaussian filter of the given FWHM. Eg, an HR+ is typically about 6mm. Set this to 0 to turn off PVC. If you don't know what to set this to, ask your PET physicist." Do you know were I can find this information for the ADNI scanners?
Thanks so much for your time and help sorting this out!
Response posted 09/03/20 by Robert Koeppe:
The partial-volume correction of PET data is quite a complicated procedure, not easily answered in such a short space. If you would e-mail me directly (koeppe@umich.edu), I will try and help. Please let me know what you are trying to accomplish. I will try and look up information about the FreeSurfer PVC, but if you can let me know how you want to use the output, that would help. True point source PSF measures, and effective PSF measures can be a bit different.
Go back to list of topics >