Table 3. Objective image quality.
| Variables | Study group 1, standard CT | Study group 2, split-filter DECT | P value |
|---|---|---|---|
| Pulmonary trunk (±SD) | |||
| CT attenuation (HU) | 428.2 (±26.5) | 344.5 (±12.9) | 0.013 |
| SNR | 16.1 (±4.6) | 27.0 (±8.2) | <0.001 |
| CNR | 13.9 (±4.6) | 22.5 (±8.0) | <0.001 |
| Right lower lobe (±SD) | |||
| CT attenuation (HU) | 366.4 (±29.0) | 327.3 (±13.3) | 0.216 |
| SNR | 14.4 (±6.2) | 25.6 (±11.9) | <0.001 |
| CNR | 12.2 (±5.9) | 21.2 (±11.4) | <0.001 |
| Left upper lobe (±SD) | |||
| CT attenuation (HU) | 365.3 (±36.9) | 305.1 (±14.5) | 0.031 |
| SNR | 12.3 (±7.6) | 23.7 (±12.9) | <0.001 |
| CNR | 10.4 (±7.0) | 19.2 (±11.8) | <0.001 |
| Descending aorta (±SD) | |||
| CT attenuation (HU) | 223.9 (±22.9) | 273.9 (±11.5) | 0.001 |
| SNR | 9.9 (±4.5) | 24.2 (±6.8) | <0.001 |
| CNR | 7.4 (±4.4) | 19.3 (±6.4) | <0.001 |
Values provided as averages and standard deviations. DECT, dual-energy computed tomography; SNR, signal-to-noise ratio; CNR, contrast-to-noise ratio; SD, standard deviation.