Table 2.
The PTV dose parameters of three plans (n=12, arithmetical mean)
| Parameters | 3D-CRT | IMRT | VMAT | 3D-CRT vs IMRT | IMRT vs VMAT | 3D-CRT vs VMAT |
| Total volume (cm3) | 896 | 896 | 896 | |||
| D95 (Gy) | 46.37±2.60 | 47.08±0.67 | 46.19±0.67 | 0.391 | 0.001 (**) | 0.816 |
| D5 (Gy) | 52.07±3.29 | 51.98±0.35 | 52.41±0.49 | 0.929 | 0.003 (**) | 0.721 |
| Dmin (Gy) | 38.96±5.01 | 34.82±4.05 | 37.44±1.83 | 0.024 (*) | 0.079 | 0.415 |
| Dmax (Gy) | 53.80±3.40 | 55.28±1.03 | 54.97±1.16 | 0.208 | 0.455 | 0.237 |
| Dmean (Gy) | 49.15±2.91 | 50.03±0.09 | 49.99±0.03 | 0.318 | 0.338 | 0.339 |
| V95% (%) | 92.73±2.80 | 93.60±2.28 | 88.79±3.08 | 0.462 | <0.0001 (****) | 0.015 (*) |
| HI | 0.14±0.2 | 0.13±0.03 | 0.16±0.03 | 0.170 | 0.009 (**) | 0.197 |
| CI | 1.69±0.52 | 1.15±0.29 | 1.06±0.26 | 0.0003 (***) | 0.002 (**) | <0.0001 (****) |
| CN | 0.63±0.19 | 0.94±0.23 | 0.92±0.23 | <0.0001 (****) | 0.360 | <0.0001 (****) |
CI, conformity index; CN, conformity number; CRT, conformal radiotherapy; D95, the dose distributed in ≥95% of the PTV; Dmax, maximum dose; Dmean, mean dose; Dmin, minimum dose; HI, homogeneity index; IMRT, intensity-modulated radiotherapy; PTV, planning target volume; V95%, volume receiving 95% of the prescribed dose; VMAT, volumetric modulated arc therapy.