Table 2.
Setup errors of Sentinel and residual setup errors of CBCT.
| The group mean (M) | Systemic errors (∑) | Random errors (σ) | PTV margin | ||
|---|---|---|---|---|---|
| X-shift (mm) | CBCT (mm) | 0.71 | 1.73 | 1.34 | 4.40 |
| Sentinel (mm) | −1.83 | 2.70 | 2.14 | 6.89 | |
| Y-shift (mm) | CBCT (mm) | 1.62 | 1.90 | 1.70 | 4.99 |
| Sentinel (mm) | −2.00 | 2.62 | 2.30 | 6.85 | |
| Z-shift (mm) | CBCT (mm) | 0.84 | 1.60 | 2.03 | 4.62 |
| Sentinel (mm) | −3.00 | 2.63 | 2.41 | 6.95 | |
| X-rotation (°) | CBCT (°) | 0.5 | 0.8 | 0.6 | — |
| Sentinel (°) | 0.3 | 0.9 | 0.8 | — | |
| Y-rotation (°) | CBCT (°) | 0.2 | 0.6 | 0.8 | — |
| Sentinel (°) | 0.2 | 1.0 | 0.9 | — | |
| Z-rotation (°) | CBCT (°) | 0.0 | 0.5 | 0.7 | — |
| Sentinel (°) | 0.0 | 0.8 | 0.9 | — |
PTV: planning target volume.