Table 3. Comparisons between Optimal Attenuation Thresholds from This Study and Visually Determined Thresholds from Previous Study (5).
| Attenuation Threshold | Fixed (320 HU) | Fixed (360 HU) | Fixed (400 HU) | Adaptive (PAavg/1.75) | Adaptive (PAavg/1.63) | Adaptive (PAavg/1.50) | Visually-Determined (120–160 HU) (5) |
|---|---|---|---|---|---|---|---|
| CT right pulmonary vascular | 68.4 ± 16.5 | 69.3 ± 17.0 | 70.0 ± 17.2 | 68.7 ± 15.9 | 69.3 ± 16.2 | 69.7 ± 16.6 | 66.3 ± 14.0 |
| p-value of paired t test | > 0.4 | > 0.7 | > 0.2 | > 0.6 | > 0.8 | > 0.5 | 0.001 |
| Pearson correlation | 0.93 | 0.93 | 0.93 | 0.91 | 0.91 | 0.91 | 0.92 |
| Mean absolute difference (%) | 4.7 | 4.6 | 4.9 | 4.8 | 4.9 | 5.0 | 5.2 |
PAavg/1.75 PAavg divided by 1.75, PAavg/1.63 PAavg divided by 1.63, PAavg/1.50 PAavg divided by 1.50.