Gamma 3%/3 mm | Gamma passing rate (%) |
p value
|
---|
PBC | MCC |
---|
Target ROI | 100 ± 0.00 | 100 ± 0.00 |
1.000
|
Periphery ROI | 98.00 ± 0.10 | 99.70 ± 0.00 |
0.037
|
Entire area | 98.10 ± 0.10 | 99.70 ± 0.00 |
0.034
|
Gamma 2%/2 mm
|
PBC
|
MCC
|
p value
|
Target ROI | 100 ± 0.00 | 100 ± 0.00 |
1.000
|
Periphery ROI | 94.20 ± 0.30 | 97.77 ± 0.12 |
0.046
|
Entire area | 94.47 ± 0.31 | 97.90 ± 0.10 |
0.050
|
- Abbreviations: PBC Pencil-beam calculation, MCC Monte Carlo calculation.
- Two gamma criteria (3%/3 mm and 2%/2 mm) with a threshold of 5% of maximal dose were used. The 3D gamma passing rate of the entire area and of each region of interest (target and periphery ROI) obtained through the pencil-beam calculation (PBC) are compared with those obtained through the Monte Carlo calculation (MCC) using the Mann–Whitney U-test. The dose was measured three times, and is shown as mean ± the standard deviation.