Table 4 Plan parameters stratified by institute
Institute Technique | A | B | C | D | E | ||
|---|---|---|---|---|---|---|---|
PTVboost | CI95 | VMAT | 1.39 | 1.35 | 1.31 | 1.43 | 1.38 |
IMRT | 1.43 | 1.42 | 1.37 | 1.55 | 1.47 | ||
PTVtotal | CI95 | VMAT | 1.51 | 1.49 | 1.54 | 1.45 | 1.51 |
IMRT | 1.58 | 1.63 | 1.70 | 1.55 | 1.65 | ||
Spinal cord | D1% (Gy) | VMAT | 39.1 | 45.6 | 47.7 | 41.1 | 43.8 |
IMRT | 39.7 | 46.7 | 48.0 | 42.0 | 45.5 | ||
Brain stem | D1% (Gy) | VMAT | 44.1 | 45.6 | 49.4 | 35.4 | 44.6 |
IMRT | 42.9 | 45.8 | 46.9 | 40.0 | 44.4 | ||
Parotid gland ipsilateral | Dmean (Gy) | VMAT | 27.6 | 26.6 | 33.3 | 23.2 | 29.3 |
IMRT | 28.5 | 28.4 | 34.2 | 25.3 | 39.0 | ||
Parotid gland contralateral | Dmean (Gy) | VMAT | 23.9 | 21.1 | 23.4 | 20.6 | 20.8 |
IMRT | 24.8 | 22.7 | 23.6 | 21.5 | 23.6 | ||
Submandibular gland contralateral | Dmean (Gy) | VMAT | 49.4 | 58.0 | 57.4 | 47.5 | 52.6 |
IMRT | 49.1 | 58.6 | 58.1 | 51.1 | 54.3 | ||
Oral cavity | Dmean (Gy) | VMAT | 40.0 | 35.2 | 41.6 | 30.7 | 36.0 |
IMRT | 42.5 | 40.2 | 43.6 | 33.5 | 37.4 | ||
Larynx | Dmean (Gy) | VMAT | 51.4 | 44.5 | 49.4 | 43.5 | 38.6 |
IMRT | 51.5 | 46.3 | 49.1 | 44.5 | 40.9 | ||
Pharyngeal constrictors° | Dmean (Gy) | VMAT | 52.0 | 45.0 | 49.8 | 43.9 | 44.7 |
IMRT | 49.0 | 45.7 | 48.8 | 44.2 | 46.6 | ||
Mandible° | Dmean (Gy) | VMAT | 48.8 | 48.0 | 50.5 | 47.6 | 48.0 |
IMRT | 49.7 | 49.9 | 51.1 | 49.3 | 51.3 | ||
Effective delivery time | (min:sec) | VMAT | 4:51 | 6:50 | -- | 5:15 | 6:41 |
IMRT | 11:47 | 12:08 | -- | 15:04 | 14:00 | ||
MUs | -- | VMAT | 600 | 602 | 540 | 774 | 698 |
IMRT | 830 | 670 | 824 | 841 | 975 |