Table 2.
Performance of virtual non-contrast CT parameters for assessing hepatic steatosis
| Hepatic steatosis grades | VNC parameter | AUC (95% CI) | Cutoff (HU) | Sensitivity (%) | Specificity (%) | |
|---|---|---|---|---|---|---|
| Mild steatosis (MRI-PDFF ≥ 5%) | LVNC | 0.795 (0.740‒0.843) | Maximal Youden index | ≤ 57.5 | 69.6 (39/56) | 83.2 (163/196) |
| > 80% sensitivity | ≤ 59.9 | 80.4 (45/56) | 63.8 (125/196) | |||
| > 80% specificity | ≤ 57.5 | 69.6 (39/56) | 83.2 (163/196) | |||
| LAIVNC | 0.806 (0.751‒0.853) | Maximal Youden index | ≤ 9.9 | 62.5 (35/56) | 88.3 (173/196) | |
| > 80% sensitivity | ≤ 12.5 | 80.4 (45/56) | 66.3 (130/196) | |||
| > 80% specificity | ≤ 10.7 | 67.9 (38/56) | 80.6 (158/196) | |||
| Moderate-to-severe steatosis (MRI-PDFF ≥ 10%) | LVNC | 0.916 (0.874‒0.947) | Maximal Youden index | ≤ 57.4 | 93.8 (15/16) | 76.7 (181/236) |
| > 80% sensitivity | ≤ 55.9 | 81.3 (13/16) | 84.8 (200/236) | |||
| > 80% specificity | ≤ 56.6 | 87.5 (14/16) | 80.5 (190/236) | |||
| LAIVNC | 0.932 (0.893‒0.960) | Maximal Youden index | ≤ 6.9 | 81.3 (13/16) | 92.4 (218/236) | |
| > 80% sensitivity | ≤ 6.9 | 81.3 (13/16) | 92.4 (218/236) | |||
| > 80% specificity | ≤ 8.9 | 87.5 (14/16) | 86.0 (203/236) | |||
VNC virtual non-contrast, AUC area under the receiver operating characteristic curve, 95% CI 95% confidence interval, MRI-PDFF magnetic resonance imaging-proton density fat fraction, L = volumetric mean CT attenuation values of the liver, S = L = volumetric mean CT attenuation values of the spleen, LAI liver attenuation index, defined as L minus S. Unless otherwise specified, numbers in parentheses are used to calculate the percentages