Table 4.
Results for nine plan groups (3 techniques + 3 MLC) for the evaluated parameters for the head-and-neck cases (average and standard deviation for five patients): QUANTEC criteria where applicable
| Head and neck | Criteria | Step–and–shoot IMRT | dmlc IMRT | VMAT | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| MLCi2− | MLCi2+ | Agility | MLCi2− | MLCi2+ | Agility | MLCi2− | MLCi2+ | Agility | ||||||||||||
| Segmentsa | – | 97.6 ± 18.3 | + | 85.8 ± 14.0 | + | 78.2 ± 11.7 | 16930 ± 2.6 | = | 16935 ± 2.7 | = | 171.2 ± 1.1 | 338.0 ± 56.7 | = | 353.8 ± 76.6 | = | 375.0 ± 57.5 | 1 | |||
| MU | – | 86.1 ± 150.5 | = | 742.2 ± 109.3 | < | 657.2 ± 95.2 | < | 777.4 ± 65.8 | < | 803.4 ± 75.9 | < | 803.9 ± 87.1 | = | 959.5 ± 98.4 | + | 983.1 ± 123.1 | + | 893.8 ± 96.3 | 2 | |
| Estimated delivery time [s] | – | 607.4 ± 92.0 | + | 571.1 ± 71.2 | + | 447.2 ± 55.7 | + | 421.2 ± 30.7 | + | 420.3 ± 25.0 | + | 323.2 ± 31.4 | + | 368.3 ± 28.6 | + | 361.7 ± 44.7 | + | 224.4 ± 23.1 | 3 | |
| PTV50 4Gy | EUD | 50.4 ⇑ | 47.7 ± 0.2 | < | 47.7 ± 0.3 | < | 47.9 ± 0.5 | < | 48.8 ± 0.6 | < | 49.1 ± 0.6 | < | 49.0 ± 0.4 | < | 49.5 ± 0.8 | < | 49.5 ± 0.7 | < | 50.1 ± 0.5 | 4 |
| Dmean | ⇑ | 52.0 ± 1.6 | < | 52.1 ± 1.5 | < | 52.1 ± 1.5 | < | 52.9 ± 1.6 | < | 52.9 ± 1.6 | < | 53.0 ± 1.5 | < | 53.1 ± 1.8 | < | 53.1 ± 1.7 | < | 53.3 ± 1.7 | 5 | |
| HIICRU | ⇓ | 0.436 ± 0.041 | + | 0.435 ± 0.041 | + | 0.431 ± 0.037 | + | 0.408 ± 0.031 | + | 0.399 ± 0.032 | + | 0.404 ± 0.036 | + | 0.380 ± 0.032 | + | 0.382 ± 0.031 | + | 0.373 ± 0.032 | 6 | |
| CI100 % | ⇑ | 0.420 ± 0.098 | < | 0.433 ± 0.090 | < | 0.429 ± 0.088 | < | 0.495 ± 0.075 | < | 0.507 ± 0.071 | < | 0.522 ± 0.066 | = | 0.523 ± 0.106 | < | 0.521 ± 0.088 | < | 0.566 ± 0.091 | 7 | |
| CI95 % | ⇑ | 0.617 ± 0.040 | < | 0.629 ± 0.038 | < | 0.634 ± 0.031 | < | 0.678 ± 0.027 | = | 0.684 ± 0.028 | = | 0689 ± 0.026 | = | 0.692 ± 0.034 | < | 0.691 ± 0.031 | < | 0.711 ± 0.033 | 8 | |
| PTV61.6 Gy | EUD | 61.6 ⇑ | 58.4 ± 1.2 | < | 58.6 ± 1.0 | < | 58.9 ± 1.3 | < | 59.9 ± 0.8 | < | 60.1 ± 0.9 | < | 60.3 ± 0.9 | = | 60.3 ± 1.0 | < | 60.2 ± 1.0 | < | 60.7 ± 0.9 | 9 |
| Dmean | ⇑ | 60.3 ± 0.7 | < | 60.4 ± 0.7 | < | 60.5 ± 0.8 | < | 61.2 ± 0.5 | < | 61.3 ± 0.6 | < | 61.4 ± 0.6 | = | 61.4 ± 0.7 | < | 61.3 ± 0.7 | < | 61.6 ± 0.6 | 10 | |
| HIICRU | ⇓ | 0.175 ± 0.035 | + | 0.172 ± 0.036 | + | 0.165 ± 0.040 | + | 0.140 ± 0.028 | + | 0.135 ± 0.030 | + | 0.127 ± 0.033 | = | 0.128 ± 0.025 | + | 0.132 ± 0.028 | + | 0.120 ± 0.027 | 11 | |
| CI100 % | ⇑ | 0.322 ± 0.084 | < | 0.326 ± 0.098 | < | 0351 ± 0.136 | < | 0.476 ± 0.113 | < | 0.501 ± 0.127 | < | 0.539 ± 0.133 | = | 0.517 ± 0.149 | < | 0.502 ± 0.132 | < | 0580 ± 0.146 | 12 | |
| CI95 % | ⇑ | 0.702 ± 0.04 | < | 0.704 ± 0.032 | < | 0.725 ± 0.048 | = | 0.775 ± 0.033 | = | 0.776 ± 0.033 | = | 0.779 ± 0.032 | = | 0.782 ± 0.037 | = | 0.779 ± 0.036 | = | 0.787 ± 0.037 | 13 | |
| Spinal cord | Dmax | 50 | 35.9 ± 4.5 | = | 35.4 ± 4.0 | = | 35.1 ± 3.9 | = | 36.5 ± 4.9 | = | 35.5 ± 4.0 | = | 35.6 ± 4.1 | = | 36.0 ± 4.1 | = | 35.7 ± 4.5 | = | 35.5 ± 3.9 | 14 |
| Brainstem | 52 | 40.1 ± 2.1 | = | 39.7 ± 2.1 | = | 39.8 ± 2.4 | = | 39.0 ± 2.9 | = | 39.6 ± 2.4 | = | 40.5 ± 2.4 | = | 40.0 ± 3.0 | = | 39.1 ± 2.8 | = | 39.7 ± 2.7 | 15 | |
| Plexus ipsilateral | 61.6 ⇓ | 58.5 ± 5.0 | = | 58.6 ± 5.6 | = | 58.6 ± 5.6 | = | 59.0 ± 5.1 | = | 59.0 ± 5.2 | = | 59.0 ± 5.1 | = | 59.0 ± 5.1 | = | 59.0 ± 5.2 | = | 58.9 ± 5.1 | 16 | |
| Plexus contralateral | 50.4 ⇓ | 51.3 ± 1.1 | = | 51.0 ± 0.7 | = | 50.8 ± 1.4 | = | 50.9 ± 0.5 | = | 51.1 ± 0.5 | = | 51.2 ± 0.7 | = | 51.5 ± 1.0 | = | 51.5 ± 0.9 | = | 51.3 ± 0.8 | 17 | |
| Mandibula | 61.6 ⇓ | 60.3 ± 3.5 | = | 60.5 ± 3.6 | = | 60.4 ± 2.6 | = | 60.8 ± 2.3 | = | 60.1 ± 1.9 | = | 61.1 ± 1.9 | = | 61.4 ± 2.3 | = | 61.1 ± 2.7 | = | 61.6 ± 2.4 | 18 | |
| Parotid contralateral | Dmean | 26 | 23.9 ± 1.7 | < | 23.6 ± 2.3 | < | 23.8 ± 0.8 | < | 25.3 ± 2.2 | = | 25.6 ± 1.7 | = | 25.1 ± 1.6 | = | 24.8 ± 1.9 | = | 24.8 ± 1.8 | = | 25.1 ± 1.7 | 19 |
| V30 Gy | 50 | 34.2 ± 6.3 | = | 33.6 ± 7.4 | = | 33.9 ± 4.5 | = | 36.3 ± 6.4 | = | 37.9 ± 5.8 | + | 36.7 ± 5.4 | + | 33.8 ± 6.8 | = | 34.3 ± 6.0 | = | 34.9 ± 6.0 | 20 | |
| Larynx | Dmean | ⇓ | 46.7 ± 1.2 | < | 46.3 ± 1.5 | < | 47.2 ± 1.0 | = | 47.2 ± 1.1 | = | 47.3 ± 0.9 | = | 47.7 ± 0.9 | = | 47.4 ± 1.8 | = | 47.2 ± 1.6 | = | 47.8 ± 1.5 | 21 |
| V50 Gy | ⇓ | 14.0 ± 12.3 | = | 13.9 ± 12.2 | = | 14.9 ± 15.2 | = | 16.7 ± 13.5 | = | 17.7 ± 14.4 | = | 19.3 ± 14.6 | = | 18.4 ± 15.4 | = | 17.5 ± 18.0 | = | 21.0 ± 18.9 | 22 | |
| A | B | C | D | E | F | G | H | I | ||||||||||||
Arrows indicate if a higher or a lower value gives the better plan. “<”,”+” or “=” indicate whether the result is lower, higher or equal to the VMATAgilty according to comparison α (bold) result on a significance level of 5 %, a for segments: results are compared within each technique to the respective Agility plan according to comparison γ (bold)