Table 3. Overview of the results.
A paired t-test (two-tailed) was performed, and the results were considered statistically significant when p-values were ≤ 0.05.
| Structure (organs at risk and remaining brain volume) | Three-dimensional conventional radiotherapy (mean±standard deviation) | Volumetric arc radiotherapy (mean±standard deviation) | t score | p-value |
| V5 (%) | 47.88 (±19.09) | 75.09 (±19.02) | -7.19 | 0.008 |
| V10 (%) | 38.53 (±16.83) | 64.46 (±19.53) | -7.51 | 0.003 |
| V20 (%) | 32.75 (±16.54) | 39.86 (±16.64) | -2.58 | 0.017 |
| V30 (%) | 28.96 (±15.92) | 22.11(±10.71) | 2.51 | 0.02 |
| V40 (%) | 24.83 (±15.88) | 10.45 (6.49) | 4.54 | 0.216 |
| V50 (%) | 20.07 (±12.05) | 3.95 (±3.25) | 6.49 | 0.644 |
| V60 (%) | 4.65 (±4.66) | 0.71 (±3.25) | 3.6 | 0.002 |
| Whole brain (mean dose, Gy) | 27.6 (±9.12) | 26.88 (±7.59) | 0.55 | 0.588 |
| Brain stem (maximum dose, Gy) | 45.54 (±17.18) | 44.99 (±15.16) | 0.4 | 0.691 |
| Optic nerve left (maximum dose, Gy) | 25.00 (±22.11) | 22.68 (±14.61) | 0.66 | 0.551 |
| Optic nerve right (maximum dose, Gy) | 27.50 (±24.87) | 25.57 (±18.24) | 0.57 | 0.576 |
| Optic chiasma (maximum dose, Gy) | 33.87 (±22.84) | 37.35 (±17.57) | -1.27 | 0.217 |
| Lens left (maximum dose, Gy) | 3.92 (±2.97) | 4.79 (±2.38) | -1.25 | 0.224 |
| Lens right (maximum dose, Gy) | 3.62 (±2.97) | 5.06 (±2.91) | -2.64 | 0.003 |
| Planning target volume V95 (%) | 96.06 (±2.60) | 98.22 (±1.41) | -3.9 | 0.001 |
| Homogeneity Index | 1.06 (±0.03) | 1.06 (±0.12) | 0.09 | 0.93 |
| Conformity Index | 0.95 (±0.02) | 0.98 (±0.01) | -4.18 | 0.001 |