Table 5.
Summary of 4-dimensional phantom study
| Scenario | Motion amplitude (mm) | Motion cycle (sec) | CBCT acquisition on motion phase | Target center alignment |
|---|---|---|---|---|
| 1 | ≤ ±5 | ≤ 6 | Any | Aligned |
| 2 | ± 5 | > 6 | Including inhalation peak and exhalation valley | Aligned |
| Incomplete inhalation peak and exhalation valley | Misaligned | |||
| 3 | > 5 | ≤ 6 | Any | Aligned, with a partial target outside the contoured ITV |
| 4 | > 5 | > 6 | Including inhalation peak and exhalation valley | Aligned, with a partial target outside the contoured ITV |
| Incomplete inhalation peak and exhalation valley | Misaligned |
Abbreviations: ITV = internal target volume.