23/03/2020
When present, the findings of COVID-19 on CT — notably peripheral ground-glass opacities — are sensitive but not specific for coronavirus; other pneumonias resemble COVID-19, particularly viral and Pneumocystis jirovecii pneumonia, cryptogenic organizing pneumonia, and acute lung injury from drug toxicity, hypersensitivity, and autoimmune diseases, to name a few pathologies. This means that false-positive errors don't occur so much from falsely labeling healthy people with COVID-19 infection but rather from falsely attributing COVID-19 in ill patients with other acute respiratory pathologies
To reduce the incidentaloma burden, radiologists should limit what's seen and see only what's clinically most relevant. In the COVID-19 chest CT protocol, the field-of-view should be restricted to avoid the thyroid and adrenals, and thick slices should be created to avoid small nodules. The changes will reduce both the number of images radiologists view — typically 1000 per study — and the radiation exposure.
Radiologists face a familiar dilemma with COVID-19, choosing between overcalling or undercalling, and both errors are costly.