Table 1 CO-RADS categories
CO-RADS | Level of suspicion | CT findings |
|---|---|---|
CO-RADS 1 | Very low | Normal or non-infectious, e.g. emphysema |
CO-RADS 2 | Low | Findings consistent with infections other than COVID-19, e.g. tree-in-bud |
CO-RADS 3 | Equivocal | Equivocal findings for pulmonary involvement of COVID-19 based on CT features that can also be found in other viral pneumonia or non-infectious causes, e.g |
Perihilar GGO | ||
Homogenous extensive GGO with or without sparing of some secondary pulmonary lobules | ||
GGO together with smooth interlobular septal thickening with or without pleural effusion in the absence of other typical CT findings | ||
Small GGO that are not centrilobular or not located close to the visceral pleura | ||
Patterns of consolidation compatible with organizing pneumonia without other typical findings of COVID-19 | ||
CO-RADS 4 | High | Findings suspicious for COVID-19 but not typical, e.g. unilateral GGO, multifocal consolidations only |
CO-RADS 5 | Very high | Typical for COVID-19, e.g. multifocal GGO, peripheral and basal distribution, GGO and consolidations, crazy paving, reversed halo, spider web sign |