Table 2.
Mean, STD, and CNR in the selected ROIs of the CatPhan©600 phantom.
| ROIs | Air 1 | Air 2 | PMP | LDPE | Polysty. | Acrylic | Delrin™ | Teflon | ERMSE | Average | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean (HU) | Cone-beam | −656.9 | −661.7 | −287.2 | −241.9 | −223.3 | −150.2 | −44.7 | 216.1 | 371.4 | ∕ |
| Fan-beam | −967.7 | −967.0 | −179.2 | −92.0 | −36.9 | 128.9 | 354.1 | 996.0 | ∕ | ∕ | |
| Al modulator | −963.4 | −951.5 | −169.6 | −61.2 | −38.9 | 109.9 | 371.6 | 1052.6 | 25.4 | ∕ | |
| Cu modulator | −1006.6 | −1004.6 | −196.7 | −104.8 | −53.6 | 116.6 | 350.8 | 1000.0 | 21.9 | ∕ | |
| Downsampled Cu | −1024.8 | −1024.1 | −160.7 | −66.1 | −2.9 | 178.2 | 424.6 | 1131.7 | 65.7 | ∕ | |
| STD (HU) | Cone-beam | 12.0 | 12.0 | 7.8 | 9.5 | 8.8 | 11.0 | 14.4 | 22.4 | ∕ | 12.2 |
| Fan-beam | 11.5 | 11.7 | 10.9 | 11.9 | 11.0 | 11.5 | 12.2 | 14.1 | ∕ | 11.2 | |
| Al modulator | 19.2 | 24.1 | 18.0 | 20.6 | 21.1 | 19.5 | 23.3 | 29.6 | ∕ | 20.9 | |
| Cu modulator | 18.9 | 21.2 | 22.2 | 21.7 | 22.9 | 23.8 | 24.8 | 28.6 | ∕ | 21.8 | |
| Downsampled Cu | 20.8 | 22.7 | 23.0 | 22.2 | 23.8 | 24.5 | 25.2 | 33.7 | ∕ | 23.4 | |
| CNR | Cone-beam | 25.5 | 23.9 | 9.1 | 5.8 | 3.4 | 0.0 | 5.3 | 13.9 | ∕ | 10.9 |
| Fan-beam | 53.8 | 54.5 | 13.2 | 9.0 | 6.4 | 1.4 | 12.0 | 37.0 | ∕ | 23.4 | |
| Al modulator | 36.1 | 31.5 | 10.3 | 5.9 | 4.6 | 0.8 | 8.2 | 25.6 | ∕ | 17.2a | |
| Cu modulator | 38.9 | 35.5 | 9.4 | 6.5 | 4.6 | 0.8 | 7.5 | 25 | ∕ | 19.2a | |
| Downsampled Cu | 37.1 | 36.0 | 9.7 | 6.6 | 4.6 | 1.2 | 8.2 | 24.6 | ∕ | 19.1a | |
a
To compensate for the attenuation of the modulator, the values are normalized to the same total patient dose.