Table 3.
Evaluations of different plans (mean and range).
| Criteria | a. Parameters for PTV | b. Parameter for OARs | c. MU and optimization time | ||||||
|---|---|---|---|---|---|---|---|---|---|
| CI | GI | D2cm (Gy) | SCmax (Gy) | V20 (%) | V10 (%) | MLD (Gy) | MU | Time(s) | |
| Two‐shell | 0.887 (0.833–0.913) | 5.194 (4.362–6.177) | 29.200 (21.956–38.463) | 10.413 (2.826–18.789) | 3.474 (1.523–6.930) | 8.019 (3.730–20.949) | 2.916 (1.455–4.654) | 2154.000 (1586–3394) | 296.800 (232–365) |
| Three‐shell | 0.887 (0.839–0.915) | 4.995 (4.144–5.816) | 27.311 (21.126–34.384) | 10.224 (2.819–18.232) | 3.357 (1.494–6.754) | 7.773 (3.609–17.587) | 2.868 (1.485–4.622) | 2160.820 (1574–3423) | 337.400 (266–421) |
| Four‐shell | 0.888 (0.834–0.917) | 4.889 (4.155–5.446) | 26.811 (20.891–31.335) | 10.086 (2.910–17.255) | 3.280 (1.468–6.738) | 7.683 (3.589–18.688) | 2.830 (1.452–4.585) | 2168.980 (1598–3225) | 390.000 (319–470) |
| Five‐shell | 0.890 (0.840–0.914) | 4.837 (4.170–5.260) | 26.564 (21.422–28.358) | 9.890 (3.028–16.897) | 3.237 (1.452–6.661) | 7.627 (3.606–18.483) | 2.821 (1.469–4.556) | 2174.740 (1622–3395) | 433.000 (363–532) |
| Six‐shell | 0.890 (0.859–0.952) | 4.789 (4.006–5.044) | 26.281 (20.754–28.639) | 9.769 (2.829–15.216) | 3.223 (1.432–6.603) | 7.607 (3.557–18.408) | 2.817 (1.457–4.571) | 2185.560 (1622–3223) | 480.400 (401–593) |
| Seven‐shell | 0.891 0.839–0.909) | 4.741 (3.987–5.031) | 26.169 (20.074–27.522) | 9.666 (3.393–16.386) | 3.220 (1.462–6.568) | 7.576 (3.583–18.380) | 2.812 (1.422–4.543) | 2190.400 (1608–3235) | 524.600 (435–652) |
| Eight‐shell | 0.891 (0.852–0.944) | 4.725 (4.004–5.027) | 26.066 (19.040–28.001) | 9.552 (3.397–15.811) | 3.214 (1.482–6.539) | 7.564 (3.706–17.321) | 2.810 (1.452–4.547) | 2192.840 (1597–3265) | 566.200 (478–691) |
| p‐value* | 0.529 | <0.001 | 0.024 | <0.001 | <0.001 | <0.001 | <0.001 | 0.531 | <0.001 |
Abbreviations: CI, conformity index; D2cm, the maximum dose outside the 2 cm of target; GI, gradient index; MLD, the mean lung dose; MU, monitor units; OARs, organs at risk; PTV, planning target volume; SCmax, the maximum dose of spinal cord; V10, V10 of total lung; V20, V20 of total lung.
*
P‐value of one‐way repeated measures ANOVA.