You need to use both to totally turn it off. There are two types of PVEs. One is due to blurring/smoothing (fixed with --psf). The other is due to multiple tissue types being in the same voxel (the tissue fraction effect (TFE))

On 1/27/2022 12:40 PM, Zhener Zhang wrote:

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Hello,

I have a question regarding the following PETSurfer command:

mri_gtmpvc --i pet.nii.gz --reg template.reg.lta --psf FWHM --seg gtmseg.mgz --default-seg-merge  --auto-mask 1 .01 --mgx .01 --o gtmpvc.output

I have been trying to run the analysis without applying partial volume correction, but it seems like there are two ways to turn it off: One is to set the point-spread function to 0 by adding “—psf 0”, The other one is to get rid of “—psf” altogether and add “—no-tfe”.

We tried both and they produced slightly different results. The second method “—no-tfe” produced lower uptake values for each ROI. Which one would you recommend to properly turn PVC off? Thanks in advance!

Best regards, Zhener

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