The importance of imaging exams in the fight against COVID-19
Posted on: 2020-03-20
Imaging exams have shown interesting findings in the fight against COVID-19. Classified as a pandemic by the World Health Organization (WHO), the new coronavirus has grown fast and exponentially worldwide since December 2019.
First, we need to understand that no imaging exam should be used for screening or as an isolated diagnosis, despite demonstrating frequent findings, particularly by computed tomography (CT). Despite showing evident findings, CT does not currently change the approach of patients with suspected or diagnosed disease, being used in critically ill patients, something that is already a standard in any other lung disease. Radiography has a secondary role, since it can be normal in a large number of cases. It is clear that the role of CT can change, with a greater understanding of the involvement of the population and more effective algorithms. That said, it is extremely relevant that radiologists are aware of the pattern of involvement by CT.
Most common CT COVID-19 findings:
- Bilateral multifocal ground-glass opacities (involving several pulmonary lobes, with predominantly peripheral distribution in the pulmonary parenchyma);
- Subsequent predominance of changes;
- Mild predilection for lower lobes;
- Association of a fine reticulate and/or septal thickening with ground-glass opacities, configuring the so-called mosaic pattern (crazy-paving) in high-resolution tomography.
CT often appears normal, even in a confirmed coronavirus case. This is due to the infection affecting the upper airways, preferably, sparing the lung parenchyma – which also happens with other viral infections. Radiologists have the responsibility to correctly guide clinicians and the medical community, always thinking about the most needy patients.