Table 3.
Analysis results of sigmoid volume and tandem length effect on the sigmoid dose volume histogram (DVH) parameters
| Sig. vol. (cm3) | DVH parameters (Mean% of planning aim dose ± 1σ) |
T. L. (cm) |
Sig. vol. (cm3) | DVH parameters (Mean% of planning aim dose ± 1σ) |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| D2cm3 | D0.1cm3 | D10 | D30 | D50 | D2cm3 | D0.1cm3 | D10 | D30 | D50 | |||
| ≤ 35 | 38.6 ± 17.3 | 54.1 ± 26.9 | 39.4 ± 18.9 | 30.7 ± 14.5 | 25.6 ± 12.0 | < 4 | ≤ 35 | 31.3 ± 14.3 | 43.7 ± 21.9 | 31.7 ± 14.9 | 24.6 ± 11.0 | 20.3 ± 8.7 |
| > 35 | 44.3 ± 13.8 | 62.6 ± 20.4 | 35.8 ± 11.1 | 25.2 ± 7.0 | 19.8 ± 5.4 | |||||||
| > 35 | 46.4 ± 14.4 | 63.6 ± 20.3 | 38.1 ± 11.8 | 27.5 ± 8.4 | 21.9 ± 6.6 | > 4 | ≤ 35 | 48.1 ± 16.4 | 67.7 ± 27.2 | 49.4 ± 19.2 | 38.7 ± 14.8 | 32.1 ± 11.7 |
| > 35 | 47.8 ± 14.9 | 64.3 ± 20.6 | 39.6 ± 12.3 | 29.0 ± 9.0 | 23.2 ± 7.1 | |||||||
Sig. vol. – sigmoid volume, T. L. – tandem length
DVH – dose volume histogram, D0.1cm3, D2cm3 – minimum dose to the most exposed 0.1 cm3, 2 cm3; D10, D30, D50 – the minimum dose to 10%, 30%, 50% of the CTV (clinical target volume)