Table 2.

µCT automatically computed biomarkers

µCT biomarkers of interest
	Name	Description	Unit	Formula
Morphological biomarkers	%Normo	Percentage of parenchyma which is normo-aerated. It reflects the number of no/mild lesions	%	Percent voxels in range [− 860, − 435]*
	%Hypo	Percentage of parenchyma which is hypo-aerated. It reflects the number of moderate lesions	%	Percent voxels in range (− 435, − 121)*
	%Non	Percentage of parenchyma which is non-aerated. It reflects the number of severe lesions	%	Percent voxels in range [− 121, 121]*
	Tissue	Lung volume without gas	mm3	${\mathrm{V}}_{\mathrm{P}02}-\mathrm{FRC}$
Functional biomarkers	$\%{\mathit{Gas}}_{P01}$	Percentage of gas volume at the end of inspiration phase (P01)	%	$\mathrm{Air}·100/{\mathrm{V}}_{\mathrm{P}01}$
	$\%{\mathit{Gas}}_{P02}$	Percentage of gas volume at the end of expiration phase (P02)	%	$FRC·100/V_{P02}$
	Tidal Volume (TV)	Volume of air exchanged between inspiration and expiration	mm3	$\mathrm{Air}-\mathrm{FRC}$