Table 4.
Image quality data of the NIM PET/CT phantom on three PET/CT systems
| PET/CT system | Sphere size (mm) | Contrast (%) | Background variability (%) | Residual error (%) |
|---|---|---|---|---|
| A | 37 | 80.27 | 2.78 | 7.46 |
| 28 | 74.14 | 3.18 | ||
| 22 | 78.28 | 3.52 | ||
| 17 | 74.59 | 3.82 | ||
| 13 | 63.12 | 4.17 | ||
| 10 | 39.95 | 4.5 | ||
| 7 | 5.61 | 4.78 | ||
| 4 | – | – | ||
| B | 37 | 82.61 | 1.9 | 8.45 |
| 28 | 76.75 | 2.42 | ||
| 22 | 72.8 | 2.98 | ||
| 17 | 72.3 | 3.68 | ||
| 13 | 61.9 | 4.53 | ||
| 10 | 43.26 | 5.5 | ||
| 7 | 24.38 | 6.78 | ||
| 4 | – | – | ||
| C | 37 | 93.26 | 2.09 | 3.24 |
| 28 | 87.21 | 2.69 | ||
| 22 | 81.12 | 3.05 | ||
| 17 | 78.54 | 3.76 | ||
| 13 | 72.08 | 5.01 | ||
| 10 | 71.27 | 6.49 | ||
| 7 | 20.06 | 7.3 | ||
| 4 | 3.22 | 10.01 |
Neither A nor B system could detect 4 mm spheres, thus, data of 4 mm spheres could not be measured