Chest CT images analysis
Three radiologists (18 years thoracic radiology specialist, 10 years
general radiologist and 2 years radiologist resident) blinded to RT-PCR
results reviewed CT images and concluded either to COVID-19 infection or
not, according to the consensual signs described in COVID-19 chest
damages7. Clinical history was available for
interpretation.
Chest CT signs were analysed according to the Fleishner Society
glossary18 : ground glass-opacities (patchy, nodular
or mixed), crazy paving (thickened intralobular and interlobular lines
in a ground glass opacity), subpleural curvilinear bands, consolidation
areas, air bubble sign, vascular dilatation, bronchial distortion,
reticular interlobular thickening, pleural effusion, pleural thickening,
number of involved lobes, inferior predominance, laterality, lung
localisation (subpleural, central or dual distribution), compatible CT
aspect of ARDS) compatible CT aspect of organized pneumonia, compatible
CT aspect of cardiac failure, lymphadenopathy, emphysematous lesions,
bronchial thickening, endobronchial secretion, centrilobular nodule, and
total lung volume involvement (0%, < 10%, 10-25%, 25-50%,
50-75%, > 75 %).
Compatible CT aspect of organized pneumonia included consolidation
(nodular, linear, perilobular, or peribronchovascular), subpleural
curvilinear bands, halo sign, and/or atoll sign.19Bronchial distortion is defined as bronchial dilatation, with irregular
contours, focalized in the areas affected by the ground glass opacities,
consolidation, or crazy paving.20