Table 4.
Dose–volume histogram comparisons for the main OARs of three plans.
| OARs | IMRT | VMAT | HT | p* | ||
|---|---|---|---|---|---|---|
| VMAT vs. IMRT | HT vs. IMRT | HT vs. VMAT | ||||
| Brainstem | ||||||
| Dmax (Gy) | 53.77 ± 1.33 | 53.16 ± 1.26 | 51.84 ± 1.95 | 0.006 | <0.001 | 0.002 |
| Spinal cord | ||||||
| Dmax (Gy) | 43.99 ± 1.03 | 42.99 ± 1.15 | 41.34 ± 1.57 | 0.022 | <0.001 | <0.001 |
| Optic nerve left | ||||||
| Dmax (Gy) | 55.46 ± 2.98 | 54.46 ± 4.13 | 52.07 ± 3.14 | 0.040 | <0.001 | 0.002 |
| Optic nerve right | ||||||
| Dmax (Gy) | 55.05 ± 2.39 | 55.11 ± 3.13 | 50.90 ± 3.24 | 0.881 | <0.001 | <0.001 |
| Optic chiasm | ||||||
| Dmax (Gy) | 42.52 ± 11.57 | 41.88 ± 11.82 | 42.67 ± 7.26 | 0.378 | 0.912 | 0.600 |
| Lens left | ||||||
| Dmax (Gy) | 7.43 ± 1.64 | 7.16 ± 1.94 | 5.47 ± 0.82 | 0.346 | <0.001 | 0.001 |
| Lens right | ||||||
| Dmax (Gy) | 7.69 ± 1.28 | 7.46 ± 1.36 | 5.82 ± 0.62 | 0.502 | <0.001 | <0.001 |
| Eye left | ||||||
| Dmax (Gy) | 35.72 ± 4.70 | 33.06 ± 6.68 | 28.13 ± 5.25 | 0.011 | <0.001 | 0.001 |
| Eye right | ||||||
| Dmax (Gy) | 35.92 ± 3.29 | 33.62 ± 5.62 | 26.62 ± 4.59 | 0.018 | <0.001 | <0.001 |
| Pituitary | ||||||
| Dmax (Gy) | 58.22 ± 4.97 | 58.54 ± 5.35 | 52.32 ± 6.78 | 0.375 | <0.001 | <0.001 |
| Mandible | ||||||
| Dmax (Gy) | 67.39 ± 3.87 | 67.76 ± 3.83 | 66.61 ± 4.20 | 0.249 | 0.234 | 0.095 |
| TMJ left | ||||||
| Dmax (Gy) | 61.07 ± 2.53 | 59.16 ± 3.54 | 57.85 ± 3.42 | 0.001 | <0.001 | 0.004 |
| TMJ right | ||||||
| Dmax (Gy) | 60.23 ± 4.88 | 58.58 ± 5.17 | 57.10 ± 5.36 | 0.016 | <0.001 | 0.027 |
| Brachial plexus left | ||||||
| Dmax (Gy) | 63.93 ± 2.19 | 64.32 ± 2.18 | 63.25 ± 3.79 | 0.132 | 0.363 | 0.177 |
| Brachial plexus right | ||||||
| Dmax (Gy) | 64.20 ± 2.63 | 64.79 ± 3.00 | 63.27 ± 4.10 | 0.074 | 0.171 | 0.022 |
| Oral cavity | ||||||
| Dmean (Gy) | 38.06 ± 1.48 | 38.44 ± 1.79 | 37.68 ± 1.57 | 0.404 | 0.356 | 0.229 |
| Parotid gland left | ||||||
| Dmean (Gy) | 33.81 ± 1.34 | 33.38 ± 1.87 | 33.64 ± 1.04 | 0.471 | 0.683 | 0.664 |
| V30 (%) | 50.58 ± 2.52 | 49.96 ± 2.70 | 45.23 ± 1.73 | 0.537 | <0.001 | <0.001 |
| Parotid gland right | ||||||
| Dmean (Gy) | 34.71 ± 1.08 | 33.86 ± 1.72 | 33.87 ± 1.13 | 0.036 | 0.048 | 0.975 |
| V30 (%) | 51.15 ± 1.68 | 50.44 ± 2.06 | 45.56 ± 2.14 | 0.359 | <0.001 | <0.001 |
| Temporal lobe left | ||||||
| Dmax (Gy) | 65.16 ± 3.94 | 64.79 ± 3.80 | 62.09 ± 3.73 | 0.071 | <0.001 | <0.001 |
| D1 (Gy) | 59.38 ± 1.26 | 59.13 ± 1.84 | 58.23 ± 1.28 | 0.429 | 0.006 | 0.028 |
| Temporal lobe right | ||||||
| Dmax (Gy) | 63.90 ± 1.39 | 64.08 ± 1.69 | 60.46 ± 0.77 | 0.659 | <0.001 | <0.001 |
| D1 (Gy) | 58.87 ± 0.85 | 59.35 ± 1.05 | 58.00 ± 1.00 | 0.080 | 0.001 | <0.001 |
| Larynx | ||||||
| Dmean (Gy) | 43.22 ± 1.08 | 41.99 ± 2.07 | 39.56 ± 0.98 | 0.024 | <0.001 | 0.001 |
| Esophagus | ||||||
| Dmean (Gy) | 30.41 ± 6.63 | 28.80 ± 6.58 | 28.18 ± 5.91 | 0.007 | <0.001 | 0.371 |
*p value was computed by paired t test.