Table 2.
Imaging beam | MV portal | MV‐CBCT | kV‐FBCT | |
---|---|---|---|---|
1.5‐MV FFF | 1.5‐MV FFF | 70–140 kV | ||
Detector | Type | aSi‐EPID | aSi‐EPID | GOS+Si CT detector |
Dimension in pixels | 1024 × 1024 | 1024 × 1024 | 816 × 24 | |
Pixel size |
0.4 mm ≈0.28 mm @ISO |
0.4 mm ≈0.28 mm @ISO |
1.0 mm;; ≈0.6 mm @ISO | |
Spatial resolution | 0.28 mm @ISO | 0.78 mm @512 × 512 | 0.97 mm @512 × 512 | |
Field of view (FOV) | 27 cm | 40 cm | 50 cm | |
Scanning range | 27 cm | 27 cm | 100 cm | |
Imaging dose | ~1 mGy | 10–30 mGy | Diagnostic: 10–50 mGy | |
Low‐dose: 3.5–5 mGy |