Table 2.
Univariate Analysis of Potential Predictors of Setup Accuracya for Pediatric CNS IGRT.
| Variablesb | VM in mm (95% CI) | P Value |
|---|---|---|
| Age | ||
| >12 years | 3.23 (2.66-3.91) | |
| ≤ 12 years | 3.26 (0.23-0.46) | .91 |
| Gender | ||
| Female | 3.38 (0.69-16.4) | .79 |
| Male | 3.29 (2.62-4.15) | |
| Baseline KPS | ||
| ≥80 | 3.00 (2.50-3.60) | .28 |
| <80 | 3.27 (2.37-4.50) | |
| Target location | ||
| Supratentorial | 3.21 (2.55-4.04) | .37 |
| Infratentorial | 2.95 (1.41-6.18) | |
| Extent of resection | ||
| Gross residual disease | 3.07 (2.34-4.02) | .49 |
| No Gross residual disease | 2.83 (1.10-7.29) | |
| Chemotherapy | ||
| Prior or concurrent with IGRT | 3.42 (2.63-4.44) | .50 |
| No prior nor concurrent IGRT | 3.10 (0.32-30.1) | |
| Baseline steroid use | ||
| Yes | 3.37 (2.90-3.91) | .22 |
| No | 3.06 (2.18-4.28) | |
| Anesthesia required | ||
| Yes | 3.08 (2.57-3.69) | .94 |
| No | 3.06 (2.38-3.95) |
Abbreviations: CBCT, cone-beam computed therapy; CI, confidence interval; CNS, central nervous system; IGRT, image-guided radiotherapy; KPS, Karnofksy Performance Status; VM, vector magnitude.
a Setup accuracy is estimated by the VM of translational treatment table shifts between setup with laser alignment alone versus with CBCT.
b Model does not converge when immobilization type was included.