Table 1. Peak CT number and CNR at different stenoses and reconstruction algorithms.
| Percent stenosis | HIR | MBIR | DLR | 2nd generation DLR |
|---|---|---|---|---|
| 25% plaque | ||||
| Peak CT number (HU) | 342.4 (338.6–354.3) | 334.5 (325.3–341.0) | 365.3 (335.6–375.1) | 357.7 (347.0–365.4) |
| CNR | 15.5 (14.7–16.1) | 15.9 (15.5–17.9) | 22.1 (20.6–23.5) | 38.3 (36.4–40.2) |
| 50% plaque | ||||
| Peak CT number (HU) | 321.5 (301.3–339.5) | 319.3 (298.1–335.3) | 336.4 (312.3–352.4) | 341.8 (321.1–349.7) |
| CNR | 14.4 (13.3–15.0) | 15.1 (14.5–16.9) | 20.4 (18.8–21.3) | 36.5 (34.6–38.2) |
| 75% plaque | ||||
| Peak CT number (HU) | 209.5 (181.8–238.9) | 216.3 (181.4–237.5) | 210.9 (180.7–234.9) | 223.4 (185.3–247.7) |
| CNR | 9.4 (8.2–10.5) | 10.2 (8.9–11.7) | 13.1 (10.5–14.3) | 24.3 (20.1–26.3) |
| Background portion | ||||
| Mean CT number (HU) | 0.6 | −1.3 | 0.1 | 0.4 |
| Standard deviation (HU) | 23.0 | 21.0 | 16.9 | 9.5 |
The peak CT number and CNR values are presented as median (interquartile range). CT, computed tomography; CNR, contrast-to-noise ratio; DLR, deep learning-based reconstruction; HIR, hybrid iterative reconstruction; MBIR, model based iterative reconstruction.