Diagnostic performance of Radiological Society of North America structured reporting language for chest computed tomography findings in patients with COVID-19.

PURPOSE: To evaluate the diagnostic performance of the RSNA structured reporting language for chest CT findings in patients with COVID-19. MATERIAL AND METHODS: Patients with suspected COVID-19 who underwent chest CT and RT-PCR tests were enrolled consecutively in this retrospective study, regardless of symptoms. Imaging findings were categorized as "typical", "indeterminate", "atypical", or "negative" according to RSNA reporting language and compared to RT-PCR. "Single, round GGO" and "single, peripheral GGO," do not fit the reporting language, were also analyzed as "indeterminate" patterns. RESULTS: Of the 1186 patients included in the analysis, the diagnosis of COVID-19 was confirmed in 388 patients. Of the 388 patients, CT findings were categorized as "typical" in 248, "indeterminate" in 77, and "negative" in 63. The sensitivity, specificity, and accuracy of "typical" findings were 63.9, 99.0, and 87.5% for COVID-19, respectively. In addition to the "typical" findings, the highest diagnostic accuracy of 92.2% was achieved when the "single, peripheral GGO" and "single, round GGO" were considered to be CT-positive. CONCLUSION: The RSNA reporting language has significant diagnostic performance for identifying COVID-19 pneumonia. CT findings that do not exactly fit the RSNA reporting language, such as "single, round GGO" and "single, peripheral GGO" improve diagnostic performance.

Evaluation of systemic involvement of Coronavirus disease 2019 through spleen; size and texture analysis

Background/aim: To investigate the changes in the spleen size, parenchymal heterogeneity, and computed tomography (CT) texture analysis features of patients diagnosed with Coronavirus disease 2019 (COVID-19) Materials and methods: The size and parenchymal structure of the spleen in 91 patients who underwent thoracic CT examination due to COVID-19 were evaluated. For the evaluation of parenchymal heterogeneity, CT texture analysis was performed using dedicated software (Olea Medical, France). The texture analysis of each case consisted of 15 first-order intensity-based features, 17 gray level co- occurrence matrix-based features, and 9 gray level run length matrix-based features. Results: A total of 91 patients (45 males, 46 females) with a mean age of 54.31 ± 16.33 years (range: 18­81) were included in the study. A statistically significant decrease in spleen size was seen in the follow-up CT examinations (p < 0.001) whereas no statistically significant difference was found between the Hounsfield unit (HU) values. The radiomics consisted of first-order intensity-based features such as 90th percentile, maximum, interquartile range, range, mean absolute deviation, standard deviation, and variance, all of which showed statistically significant differences (p-values: < 0.001, < 0.001, 0.001, 0.003, 0.001, 0.001, and 0.004, respectively). "Correlation" as a gray level co-occurrence matrix-based feature and "gray level nonuniformity" as a gray level run length matrix-based feature showed statistically differences (p-values: 0.033 and < 0.001, respectively). Conclusions: Although COVID-19 manifests with lung involvement in the early stage, it can also cause systemic involvement, and the spleen may be one of its target organs. A decrease in the spleen size and parenchymal microstructure changes can be observed in the short follow-up time. It is hoped that the changes in the parenchymal microstructure will be demonstrated by a noninvasive method: texture analysis.

Chest CT findings in RT-PCR positive asymptomatic COVID-19 patients.

PURPOSE: To investigate chest computed tomography (CT) findings in asymptomatic patients tested positive for coronavirus disease (COVID-19) by reverse transcription-polymerase chain reaction (RT-PCR). MATERIAL AND METHODS: The chest CT images of 64 patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who were RT-PCR test-positive but asymptomatic were retrospectively evaluated for the appearance and distribution of abnormal parenchymal findings. RESULTS: Of the 64 patients (mean age 59.4 ± 12; range 23-85), 42 (65%) were female, and 22 (35%) were male, and 16 (25%) of the patients had no abnormal findings on chest CT. Of the remaining 48 patients, lung involvement was bilateral in 32 (67%). Right upper lobe in 26 (54%), right middle lobe in 20 (42%), right lower lobe in 38 (79%), left upper lobe in 27 (56%), and left lower lobe were affected in 34 (71%) patients. The mean number of opacities detected in patients was 7.5 ± 5.7. The opacities were located only peripherally/subpleural in 22 (46%), only centrally/peribronchovascular in 5 (10%), and mixed in 21 (44%) patients. The frequency of pure ground glass opacities (GGO) was 63% GGO with a crazy-paving pattern or consolidation was 33%. Pure consolidation was detected in only two (4%) patients. Parenchymal opacities were only round in 27 (56%), only geographic demarcated in 3 (6%), only patchy in 2 (4%), and mixed in 16 (33%) patients. CONCLUSION: Chest CT was normal in only one-quarter of the asymptomatic patients. CT findings in asymptomatic COVID-19 patients were often peripherally located, mostly round-shaped GGO.

Clinical and Laboratory Characteristics of COVID-19 Cases Followed in Selcuk University Faculty of Medicine

Objective: Understanding the natural course of COVID-19 and determining its clinical findings are essential for early diagnosis and treatment. In this study, we aimed to investigate clinical and laboratory characteristics of cases followed with a diagnosis of COVID-19 in Selcuk University Faculty of Medicine Department of Infectious Diseases and Clinical Microbiology. Methods: Among patients followed with a diagnosis of possible/definitive COVID-19, those with a positive SARS-CoV-2 RT-PCR test were evaluated retrospectively in terms of their clinical, laboratory and thorax computed tomography (CT) data. Results: Among 407 patients followed with a diagnosis of possible/definitive COVID-19, 149 (36.6%) were SARS-CoV-2 RT-PCR test-positive. 82 (55%) of the patients were female and 67 (45%) were male. Mean age was 49.3 +/- 7.6 years. 11 (7.4%) were health care workers. While the most common symptom was cough with 46.3%, fever was observed in 29.5%, sore throat in 27.5% and malaise in 26.8% of the patients. 94 (63.1%) of the patients had underlying diseases. Hypertension and diabetes mellitus were the most common underlying disease. Laboratory findings were leukopenia in 12 (8.1%), lymphopenia in 34 (22.8%), thrombocytopenia in 24 (16.1%), elevated D-dimer levels in 43 (28.9%), elevated lactate dehydrogenase levels in 73 (49%), and elevated C-reactive protein (CRP) levels in 45 (30.2%) patients. While 71 (47.6%) of the patients had normal thorax CT, 43 (28.9%) had mild pneumonia, and 35 (23.5%) moderate pneumonia. D-dimer and CRP levels were higher in those with pneumonia than those without pneumonia (p=0.001 and p=0.001, respectively). As the pneumonia level increased, the increase of D-dimer and CRP levels became evident (p=0.003 and p=0.001, respectively). Conclusions: The clinical course of COVID-19 patients varies. It is noteworthy that there is a positive correlation between the severity of pneumonia and the increase in D-dimer and CRP levels in COVID-19.