Boxplots distribution corresponding to the FWHM estimation of amyloid PET images in both axial and in-plane directions for several sites in the ADNI study cohort.
The figure shows the boxplot distribution across subjects of the FWHM estimation for several ADNI sites. Thus, all subjects belonging to the same site ID had amyloid images scanned with the same scanner manufacturer, scanner model, and reconstruction parameters.
The figure shows that the mean value of the in-plane resolution estimation tends to be very similar or less than the axial resolution estimation for most of the site IDs.
The most interesting case where the mean FWHM in the xy-plane (FWHMxy) is evidently larger than the FWHM in the z-plane (FWHMz) is the site ID labelled as 153, which corresponds to a Biograph20_mCT/SIEMENS model with and image matrix of 256 x 256 x 81 voxels and voxel size of 1.6 x 1.6 x 2.02 mm.