Clinical Relevance and Follow-Up of Incidental CT Imaging Findings for COVID-19 Diagnosis: A Retrospective Analysis

Background: /Objectives: To evaluate the prevalence of incidental findings in thoracic computed tomography (CT) performed because of COVID-19 and their potential impact on patient management. Methods: This retrospective analysis included 683 CT scans from 327 patients who underwent CT imaging of the thorax with or without the application of intravenous contrast-agents because of the primary indication of COVID-19. Radiological findings were categorized according to the COVID-19 Pneumonia Imaging Classification by 4 independent readers. Incidental findings were categorized according to a scale ranging from 0 (no patient impairment) to 3b (severe permanent impairment. Results: In the 683 CT-scans, typical COVID-19 findings were present in 273 scans (40.0%), atypical signs in 97 (14.2%), indeterminate findings in 40 (5.9%), and no signs of COVID-19 in 273 (40.0%). Incidental findings were reported in 93 out of 683 cases (13.6%), of which 63 (67.0%) were classified as category 0, 12 (12.8%) as category 1, 9 (9.6%) as category 2a, none (0.0%) as category 2b, 5 (5.3%) as category 3a, and 5 (5.3%) as category 3b. Conclusions: CT scans of the thorax for COVID-19 show a substantial proportion of incidental findings that require further investigation.