Table 4.
The changes of geometric parameters of the imaging system brought about by the specific parameters varied in different evaluations. Δϕ, ΔR, and Δz are the changes in the gantry angle, rotation radius and distance from the rotation plane, respectively. ΔF, Δu, and Δv are the changes of the focal distance, and the two translational offsets of the imager in the uv plane, respectively; α and β describe the changes in the tilting of the imager.
| Evaluation | Parameter varied | Range varied | Δϕ (°) | ΔR (mm) | Δz (mm) | ΔF (mm) | Δu (mm) | Δv (mm) | α (°) | β (°) |
|---|---|---|---|---|---|---|---|---|---|---|
| II.D.4 | SID | 1300–1600 mm | 0.01 | 1.06 | 0.08 | ⋯ | 0.23 | 0.75 | 0.34 | 0.13 |
| II.D.5 | Imager off center | ±20 mm | 0.00 | 0.27 | 0.08 | 0.12 | ⋯ | ⋯ | 0.61 | 0.25 |
| II.D.7 | Gantry angle | ±45° | ⋯ | 0.28 | 0.05 | 0.50 | 0.02 | 0.06 | 0.13 | 0.05 |