Table 4.
The percentage differences of doses and volumes for the OARs between vIDC using three dose grid sizes and TPS using G1.0.
| Grid size | Dosimetric parameter | OARs (percent difference compared with the TPS) | |||
|---|---|---|---|---|---|
| Bladder | Rectum | Sigmoid | |||
| (Mean ± std) | (Mean ± std) | (Mean ± std) | |||
| TPS | G1.0 | D10cc | 222.15 ± 75.24 | 132.80 ± 67.19 | 252.25 ± 62.63 |
| D2cc | 324.25 ± 101.81 | 195.85 ± 85.42 | 367.40 ± 76.61 | ||
| D0.1cc | 448.45 ± 133.95 | 271.10 ± 117.63 | 543.30 ± 138.11 | ||
| Mean volume of OARs (cm3) | 57.75 | 45.28 | 168.69 | ||
| vIDC | G2.5 | D10cc | 232.25 ± 75.45 | 134.4 ± 66.67 | 259.50 ± 62.75 |
| (4.34) | (2.25) | (3.08) | |||
| D2cc | 343.85 ± 110.17 | 197.60 ± 86.65 | 381.90 ± 76.97 | ||
| (5.65) | (0.92) | (4.14) | |||
| D0.1cc | 487.80 ± 150.73 | 276.75 ± 120.89 | 564.30 ± 131.48 | ||
| (8.18) | (1.95) | (4.43) | |||
| Mean volume of OARs (cm3) | 62.25 | 49.26 | 180.49 | ||
| |8.71| | |10.41| | |8.12| | |||
| G1.0 | D10cc | 222.40 ± 76.29 | 127.40 ± 64.59 | 248.20 ± 61.02 | |
| (−0.11) | (−4.04) | (−1.55) | |||
| D2cc | 327.70 ± 104.35 | 188.15 ± 81.57 | 363.35 ± 73.75 | ||
| (1.12) | (−3.82) | (−0.97) | |||
| D0.1cc | 458.60 ± 139.53 | 260.35 ± 112.72 | 532.90 ± 125.73 | ||
| (1.97) | (−3.89) | (−1.53) | |||
| Mean volume of OARs (cm3) | 57.03 | 44.83 | 165.94 | ||
| |1.43| | |1.12| | |1.82| | |||
| G0.5 | D10cc | 219.60 ± 75.45 | 125.15 ± 64.20 | 244.85 ± 60.48 | |
| (−1.36) | (−6.20) | (−2.90) | |||
| D2cc | 322.85 ± 102.68 | 185.20 ± 80.04 | 358.05 ± 73.34 | ||
| (−0.63) | (−5.26) | (−2.46) | |||
| D0.1cc | 450.60 ± 136.32 | 255.50 ± 110.38 | 523.65 ± 124.75 | ||
| (0.29) | (−5.62) | (−3.30) | |||
| Mean volume of OARs (cm3) | 55.48 | 43.53 | 161.51 | ||
| |4.42| | |4.53| | |4.81| | |||
OARs, organs at risk; vIDC, volumetric independent dose calculation; TPS, treatment planning system.