COVID-19 imaging: Diagnostic approaches, challenges, and evolving advances

Figure 1 Flowchart depicting four scenarios in which imaging is indicated in the diagnostic work up and management of coronavirus disease-2019. A: Moderate to severe features are defined as the presence marked pulmonary damage and dysfunction; B: Mild features are defined as the absence of marked pulmonary damage and dysfunction & high risk factors for disease progression are defined as the presence of underlying comorbidities such as cardiovascular disease, diabetes, hypertension, and an immunocompromised status; C: Moderate/high pre-test probability is defined as a high background prevalence of disease in the surrounding area and a likely scenario of exposure to severe acute respiratory syndrome coronavirus 2; D: Moderate to severe features are defined as the presence marked pulmonary damage and dysfunction; E: Imaging refers to either the use of chest radiography (CXR) or chest computed tomography (CT). The employment of either is dependent upon time of presentation (early = chest CT, late = CXR), resources (CT scanner availability), and clinical expertise (preference of physician for a particular imaging modality); F: Additional imaging would ideally be CXR as it allows for rapid assessment of an evolving clinical status; G: Repeat test includes RT-PCR. Imaging features of COVID-19 disease on CXR include a bilateral, posterior and peripheral pattern, with a predominance in the lower lung fields; the most commonly reported interstitial abnormalities are reticular and reticulonodular patterns and the most commonly reported alveolar findings are hazy pulmonary opacities. This flow chart was adapted and modified based on the Fleischner Society’s article from April of 2020 (Rubin). COVID-19: Coronavirus disease-2019; RT-PCR: Real time-polymerase chain reaction.