Table 1.
The direct posterior (gantry angle 180°), maximum, and average beam attenuations (in percentage) measured with eight different couch inserts with energies of 6 and 15 MV. The average beam attenuation was calculated between gantry angles of 100°–180°. The couch inserts are in descending order with respect to attenuation with a direct posterior 6 MV beam.
| 6 MV | 15 MV | |||||
|---|---|---|---|---|---|---|
| GA 180° | Max. | Average (100°–180°) | GA 180° | Max. | Average (100°–180° | |
| BrainLAB | 3.6 | 8.7 | 5.0 | 2.4 | 5.9 | 3.3 |
| Qfix kVue Standard | 2.1 | 5.2 | 2.9 | 1.4 | 3.3 | 1.9 |
| MEDTEC | 1.9 | 7.1 | 2.9 | 1.5 | 5.0 | 2.1 |
| Varian Exact IGRT | 1.9 | 4.7 | 2.4 | 1.3 | 3.1 | 1.6 |
| DIGNITY AirPlate | 1.9 | 3.6 | 2.3 | 1.2 | 2.4 | 1.5 |
| Universal Sandwich Panel | 1.5 | 7.3 | 2.8 | 1.0 | 5.0 | 2.0 |
| Qfix kVue DoseMax | 1.3 | 8.1 | 2.2 | 1.0 | 5.4 | 1.4 |
| Varian Grid Insert | 0.3 | 10.8 | 1.3 | 0.2 | 7.4 | 0.9 |