Adapted RSNA consensus guidelines for reporting CT findings related to COVID-19^{^a}

CT Imaging Appearance	Pulmonary CT Findings	Suggested Reporting Language
Typical	Crazy paving	“Commonly reported imaging features of (COVID-19) pneumonia are present. Other processes such as influenza pneumonia and organizing pneumonia, as can be seen with drug toxicity and connective tissue disease, can cause a similar imaging pattern.”
	Bilateral
	Peripheral
	GGO
	Bilateral
	Peripheral
	Multifocal
	Rounded
	Organizing pneumonia

Indeterminate	No typical features and	“Imaging features can be seen with (COVID-19) pneumonia, though are nonspecific and can occur with a variety of infectious and noninfectious processes.”
	GGO
	Multifocal
	Diffuse
	Perihilar
	Unilateral
	Nonrounded

Atypical	No typical or indeterminate features and	“Imaging features are atypical or uncommonly reported for (COVID-19) pneumonia. Alternative diagnosis should be considered.”
	Isolated lobar or segmental consolidation without GGO
	Centrilobular nodules
	Cavitation
	Smooth interlobular septal thickening with pleural effusion

Negative	No CT features of pneumonia	“No CT findings present to indicate pneumonia. (Note: CT may be negative in the early stages of COVID-19.)”

↵a This table was adapted from Simpson et al.⁶ Crazy paving is rounded ground glass opacification associated with inter- and intralobular septal thickening. Organizing pneumonia is a focus of GGO with peripheral consolidation previously described as “atoll sign” or “reverse halo sign.”