Computed Tomography Features of Coronavirus Disease 2019 (COVID-19)

Abstract

Coronavirus Disease 2019 (COVID-19) pneumonia has become a global pandemic. Although the rate of new infections in China has decreased, currently, 169 countries report confirmed cases, with many nations showing increasing numbers daily. Testing for COVID-19 infection is performed via reverse transcriptase polymerase chain reaction, but availability is limited in many parts of the world. The role of chest computed tomography is yet to be determined and may vary depending on the local prevalence of disease and availability of laboratory testing. A common but nonspecific pattern of disease with a somewhat predictable progression is seen in patients with COVID-19. Specifically, patchy ground-glass opacities in the periphery of the lower lungs may be present initially, eventually undergoing coalescence, consolidation, and organization, and ultimately showing features of fibrosis. In this article, we review the computed tomography features of COVID-19 infection. Familiarity with these findings and their evolution will help radiologists recognize potential COVID-19 and recognize the significant overlap with other causes of acute lung injury.

Role of computed tomography in COVID-19

“…First, a number of factors influence the performance of RT-PCR, including the site of specimen, the stage of disease, the viral load, and the reliability of the testing kit. 47 , 52 The sensitivity of RT-PCR ranged from 60% to 89%, depending on the specimen site (throat sample vs. sputum, respectively). 53 In particular, a lower sensitivity of RT-PCR has been reported in elderly patients, reflecting the possible poor cooperation of the subjects leading to improper sampling.…”

Chest CT target sign in a couple with COVID-19 pneumonia

“…The CT target sign that we describe here is distinct from the reversed halo sign and the perilobular opacity because of the presence of a nodular opacity in the center of the ring-like opacity. Perilobular opacities and the reversed halo sign are a common finding in organizing pneumonia and have been described in a number of patients with COVID-19 pneumonia ( 1 , 7 , 8 ) . The target sign on chest CT is quite distinct from the target sign seen in diseases of the bowel where it typically reflects the presence of submucosal edema, inflammation, or both ( 11 ) .…”

“…ity, crazy paving pattern, and consolidation, commonly with a rounded contour and peripheral distribution, but not uncommonly multifocal or diffuse, as well as findings with a pattern suggestive of organizing pneumonia including reverse halo sign and perilobular opacities (1,(5)(6)(7)(8) . Other common manifestations include thickening/enlargement of peripheral pulmonary vessels, commonly within areas of ground-glass opacity (8)(9)(10) .…”

“…Other common manifestations include thickening/enlargement of peripheral pulmonary vessels, commonly within areas of ground-glass opacity (8)(9)(10) . Less common pulmonary manifestations of COVID-19 include irregular nodules, nodules with CT halo sign, and, in the later stages, bronchial dilatation/distortion and reticulation (1,(5)(6)(7)(8)(9) .…”

“…Chest CT has a high sensitivity (93% to 97%) when the RT-PCR is used as the gold standard for diagnosis, but low specificity (25% to 53%), because of the overlap of the CT findings with those of other pulmonary infections, including influenza H1N1, as well as pulmonary inflammatory processes related to adverse drug reactions, complications of connective tissue disease, vasculitis, etc. ( 5 - 7 ) .…”