Table 1 Characteristics of the Discovery MI and Gemini TF PET-CT systems
PET-CT system | Discovery MI | Gemini TF |
|---|---|---|
Crystal material | LYSO | LYSO |
Amplifier | SiPM | PM-tubes |
Number of rings | 4 | 3 |
Size of crystals [mm3] | 3.95 × 5.3 × 25 | 4.0 × 4.0 × 22 |
Axial FOV [mm] | 200 | 180 |
Bore diameter [mm] | 700 | 700 |
Overlap [%] | 23.9 | 50 |
NEMA Sensitivity [cps/kBq] | 13.8 | 7.0 |
FWHM axial @1 cm [mm] | 4.7 | 5.8 |
Coincidence window width (ns) | 4.9 | 6 |
Timing resolution (ps) | 382 | 600 |
Lower energy threshold (keV) | 425 | 440 |
Matrix | 256 × 256 | 144 × 144 |
Pixel size (mm2) | 2.7 × 2.7 | 4.0 × 4.0 |
Slice thickness [mm] | 2.79 | 4.0 |
Image planes in the axial FOV | 71 | 45 |
Number of CT slice | 128 | 16 |