Coronavirus Disease 2019 (COVID-19) in Italy: Double reading of chest CT examination
Abstract OBJECTIVETo assess the performance of the second reading of chest Compute Tomography (CT) examinations by expert radiologists in patients with discordance between the reverse transcription real-time fluorescence polymerase chain reaction (RT-PCR) test for COVID-19 viral pneumonia and the first CT report.MATERIALS AND METHODS.Three hundred seventy-heigth patients were included in this retrospective study (121 women and 257 men; 71 years of median age - range, 29–93 years) subjected to RT-PCR test for suspicious COVID-19 infection. All patients were subjected to CT examination in order to evaluate the pulmonary disease involvement by COVID-19. CT images were reviewed first by two radiologists who identified COVID-19 typical CT patterns and then reanalyzed by anoter two radiologists using a CT structured report for COVID-19 diagnosis.RESULTS.The median temporal window between RT-PCRs execution and CT scan was 0 days with a range of [-9, 11] days. RT-PCR test was resulted positive in 328/378 (86.8%). Discordance between RT-PCR and CT findings for viral pneumonia was revealed in 60 cases. The second reading changed the CT diagnosis in 16/60 (26.7%) cases contributing to increase the concordance with the RT-PCR. Among these 60 cases, 8 were false negative with positive RT-PCR, and 36 were false positive with negative RT-PCR. Sensitivity, specificity, positive predictive value and negative predictive value of CT were respectively of 97.3%, 53.8%, 89.0%, and 88.4%.CONCLUSION.Double reading of CT could increase the diagnostic confidence of radiological interpretation in COVID-19 patients. Using expert second readers could reduce the rate of discrepant cases between RT-PCR results and CT diagnosis for COVID-19 viral pneumonia.