Table 1 Characteristics of the Discovery MI and Discovery 690 scanners
PET/CT system | Discovery MI | Discovery PET/CT 690 |
|---|---|---|
Crystal material | LYSO/LBS | LYSO/LBS |
Light detection | SiPM | PMT |
Number of detector rings | 4 | 3 |
Number of crystals | 19584 | 13824 |
Size of crystals [mm3] | 3.95 × 5.3 × 25 | 4.2 × 6.3 × 25 |
Slice thickness [mm] | 2.79 | 3.27 |
Axial FOV [mm] | 200 | 157 |
FOV [mm] | 700 | 700 |
Overlap [%]a | 23.9 | 23.4 |
NEMA Sensitivity [cps/kBq] | 13.8 | 6.9 |
Image planes in the axial FOV | 71 | 47 |
FWHM axial @1 cm [mm] | 4.7 | 5.2 |
Coincidence window width (ns) | 4.9 | 4.9 |
Coincidence timing resolution (ps) | 375.4 | 544.3 |
Lower energy threshold (keV) | 425 | 425 |