Table 2 Dosimetric characteristics of grid fields compare to open fields. The absolute uncertainties for calculated TPR20/10 and dmax are 0.009 and 1.0 mm, respectively.
From: Beam quality and the mystery behind the lower percentage depth dose in grid radiation therapy
10 × 10 cm2 | 20 × 20 cm2 | ||||
|---|---|---|---|---|---|
TPR20/10 | dmax (mm) | Output factor | dmax (mm) | Output factor | |
Open field | 0.678 | 15.5 | 1.000 | 14.5 | 1.045 |
Brass grid | 0.648 | 13.5 | 0.782 | 13.5 | 0.813 |
Cerrobend grid | 0.645 | 13.5 | 0.772 | 13.5 | 0.790 |
