Attenuation values and image-quality comparison between photon-counting detector low-energy and high-energy bin images for gray matter, white matter, and CSF
| Low-Energy Bin (22–52 keV)a | High-Energy Bin (52–120 keV)a | P Value | |
|---|---|---|---|
| Attenuation values (HU) | |||
| Basal nuclei GM | 41.5 ± 2.1 | 38.3 ± 2.1 | <.001 |
| Internal capsule WM | 30.9 ± 2.7 | 29.5 ± 2.0 | .03 |
| Lateral ventricle (CSF) | 7.2 ± 2.1 | 4.7 ± 1.9 | <.001 |
| Image-quality metrics | |||
| GM noise (HU) | 5.4 ± 1.2 | 4.5 ± 0.9 | .004 |
| WM noise (HU) | 5.0 ± 1.6 | 3.9 ± 0.7 | .01 |
| CSF noise (HU) | 4.9 ± 0.9 | 4.7 ± 1.2 | .36 |
| GM SNR | 8.2 ± 2.1 | 8.9 ± 1.8 | .11 |
| WM SNR | 6.7 ± 1.9 | 7.7 ± 1.6 | .05 |
| GM–WM contrast (HU) | 10.6 ± 2.3 | 8.8 ± 2.5 | .02 |
| GM–WM CNR | 1.5 ± 0.5 | 1.5 ± 0.5 | .96 |
↵a Values are means ± SD.