Table 5.
Comparison of dosimetric parameters between VMAT and IMRT
| Variable | Volume (mean ± sd, cm3) VMAT | IMRT | P-value | Ratio of volume and dose (mean ± sd, %) VMAT | IMRT | P-value |
|---|---|---|---|---|---|---|
| TLV | 3171.2 ± 470.64 | 3215.8 ± 729.71 | 0.795 | |||
| V5 | 2344.4 ± 542.91 | 2041.1 ± 738.73 | 0.091 | 0.74 ± 0.10 | 0.63 ± 0.14 | 0.002 |
| V10 | 1591.2 ± 378.25 | 1440.9 ± 547.13 | 0.250 | 0.50 ± 0.11 | 0.44 ± 0.10 | 0.023 |
| V15 | 1013.0 ± 265.56 | 983.48 ± 381.53 | 0.745 | 0.32 ± 0.08 | 0.30 ± 0.07 | 0.319 |
| V20 | 707.49 ± 203.59 | 640.59 ± 233.55 | 0.254 | 0.22 ± 0.06 | 0.19 ± 0.05 | 0.066 |
| V25 | 500.48 ± 169.91 | 428.06 ± 172.64 | 0.109 | 0.16 ± 0.05 | 0.13 ± 0.04 | 0.029 |
| V30 | 363.69 ± 146.39 | 287.86 ± 132.73 | 0.037 | 0.10 ± 0.04 | 0.09 ± 0.03 | 0.011 |
| MLD (Gy) | 13.12 ± 2.36 | 11.59 ± 2.18 | 0.009 |
IMRT, intensity modulated radiation therapy; MLD, mean lung dose; sd, standard deviation; TLV, total lung volume; V5, V10,V15,V20,V25, V30, percentage of lung receiving ≥ 5 Gy (through 30 Gy); VMAT, volumetric modulated arc therapy.