Table 2.
Specifications of the four PET scanners used in this study
| Discovery IQ | Discovery 600 | Discovery ST | Gemini TF | |
|---|---|---|---|---|
| Matrix size | 192 × 192 | 192 × 192 | 128 × 128 | 144 × 144 |
| Slice thickness | 3.26 mm | 3.27 mm | 3.27 mm | 4 mm |
| Pixel size | 2.6 mm | 2.6 mm | 4.7 mm | 4 mm |
| FOV | 500 mm | 500 mm | 600 mm | 576 mm |
| Reconstruction | QCHD | VPHDS | VPHD | BLOB-OS-TF |
| Subset/iteration | Not availablea | 16/3 | 21/2 | 33/3 |
| Acquisition time (min/bed) | 2–2.5 (2.5)b | 1.5–3 (2.5)b | 2 (2)b | 2 (2)b |
| Postfiltering FWHM (mm) | Not available | 3 | 4.29 | Not available |
BLOB-OS-TF blob ordered-subsets time-of-flight, FOV field of view, FWHM full width at half maximum, PET positron emission tomography, QCHD Q. Clear HD (a type of Bayesian penalized likelihood, GE Healthcare), VPHD VUE-point HD, VPHDS VPHD with point spread function
aThe definition of the number of subsets and its iteration does not exist in Bayesian penalized likelihood reconstruction because of its regularization algorithm
bThe median acquisition time of the scanner is described in parentheses