Table 1. Features Analyzed by Algorithms with Units and Definitions.
| Metric Name | Unit | Definition |
|---|---|---|
| Pulmonary metrics | ||
| Lung volume | mL | Total volume of the lung |
| PO | % | Percentage of volume of the lung affected by opacities, equivalent to GGO and consolidation |
| PHO | % | Percentage of volume of the lung affected by high HU opacities (equal to or above -200 HU), equivalent to consolidations |
| %LowHU | % | Percentage of volume of the lung with low attenuation, defined as < -950 HU |
| LL# | N | Number of lung lesions detected (GGO or consolidations) |
| LSS | N | Sum of severity scores for each of the five lung lobes* |
| LHOS | N | Sum of severity scores for each of the five lung lobes, consolidation only* |
| Cardiovascular metrics | ||
| TPV | mL | Total pericardial volume. This includes the heart as well as pericardial structures like fat and/or effusion |
| QCC | mm3 | Total volume of coronary calcifications. Only available for CT without contrast |
| D_AAsc | mm | Diameter of ascending aorta at the level of the right pulmonary artery |
| D_Arch | mm | Diameter of aorta, midway through aortic arch region |
| D_ADsc | mm | Diameter of descending aorta, midway between the branching of the subclavian artery and celiac artery |
*Severity scores calculated as follows. 0: lobe not affected by GGO/consolidation, 1: 1–25% of lobe volume affected, 2: 25–50%, 3: 50–75%, 4: 75–100%. GGO = ground-glass opacity, HU = Hounsfield unit, QCC = quantification of coronary calcification