Chest CT imaging features of Covid-19 patients: Single center observational study

Objective: The aim of this study was to explore the chest Computer Tomography (CT) features of COVID-19 patients and compare the diagnostic performance of chest CT with that of RT-PCR at our center. Material and Methods: The study was conducted by retrospectively scanning the files of patients admitted to the Emergency Department of Karaman State Hospital under suspicion of COVID-19 between March 15 and May 18, 2020. The study included 218 patients (124 males, 94 females, 1-90 years of age, median 48.5) who met the inclusion criteria. Chest CT scan findings were recorded in detail by two radiologists with experience in chest radiology. Furthermore, the CT findings were categorized into four groups in the form of typical, indeterminate, atypical, and negative CT according to the structured reporting system. Results: The RT-PCR results were positive in 41% of 139 cases with positive CT results, while the RT-PCR results were positive in 15.2% of the cases with negative CT results. Regarding the analysis between CT and RT-PCR, the sensitivity was 82.61%, the specificity was 44.97%, the PPV was 41.01%, the NPV was 84.81%. The positivity rate was 82.9% in those with typical imaging findings, 51.5% in those assessed as indeterminate. Those with a typical appearance had a higher rate of positivity than others. Conclusion: The chest CT scan was found to have a high correlation with the RT-PCR in the patients with typical imaging findings in CT. The specificity was found to be low in the CT scan findings without subgroup analysis.