Combined Model of Quantitative Evaluation of Chest Computed Tomography and Laboratory Values for Assessing the Prognosis of Coronavirus Disease 2019.

PURPOSE: To assess the prognostic power of quantitative analysis of chest CT, laboratory values, and their combination in COVID-19 pneumonia. MATERIALS AND METHODS: Retrospective analysis of patients with PCR-confirmed COVID-19 pneumonia and chest CT performed between March 07 and November 13, 2020. Volume and percentage (PO) of lung opacifications and mean HU of the whole lung were quantified using prototype software. 13 laboratory values were collected. Negative outcome was defined as death, ICU admittance, mechanical ventilation, or extracorporeal membrane oxygenation. Positive outcome was defined as care in the regular ward or discharge. Logistic regression was performed to evaluate the prognostic value of CT parameters and laboratory values. Independent predictors were combined to establish a scoring system for prediction of prognosis. This score was validated on a separate validation cohort. RESULTS: 89 patients were included for model development between March 07 and April 27, 2020 (mean age: 60.3 years). 38 patients experienced a negative outcome. In univariate regression analysis, all quantitative CT parameters as well as C-reactive protein (CRP), relative lymphocyte count (RLC), troponin, and LDH were associated with a negative outcome. In a multivariate regression analysis, PO, CRP, and RLC were independent predictors of a negative outcome. Combination of these three values showed a strong predictive value with a C-index of 0.87. A scoring system was established which categorized patients into 4 groups with a risk of 7 %, 30 %, 67 %, or 100 % for a negative outcome. The validation cohort consisted of 28 patients between May 5 and November 13, 2020. A negative outcome occurred in 6 % of patients with a score of 0, 50 % with a score of 1, and 100 % with a score of 2 or 3. CONCLUSION: The combination of PO, CRP, and RLC showed a high predictive value for a negative outcome. A 4-point scoring system based on these findings allows easy risk stratification in the clinical routine and performed exceptionally in the validation cohort. KEY POINTS: · A high PO is associated with an unfavorable outcome in COVID-19. · PO, CRP, and RLC are independent predictors of an unfavorable outcome, and their combination has strong predictive power. · A 4-point scoring system based on these values allows quick risk stratification in a clinical setting. CITATION FORMAT: · Scharf G, Meiler S, Zeman F et al. Combined Model of Quantitative Evaluation of Chest Computed Tomography and Laboratory Values for Assessing the Prognosis of Coronavirus Disease 2019. Fortschr Röntgenstr 2022; 194: 737 - 746.

CT Features of COVID-19 Pneumonia Differ Depending on the Severity and Duration of Disease.

BACKGROUND: CT is important in the care of patients with COVID-19 pneumonia. However, CT morphology can change significantly over the course of the disease. To evaluate the CT morphology of RT-PCR-proven COVID-19 pneumonia in a German cohort with special emphasis on identification of potential differences of CT features depending on duration and severity of disease. METHOD: All patients with RT-PCR-proven COVID-19 pneumonia and chest CT performed between March 1 and April 15, 2020 were retrospectively identified. The CT scans were evaluated regarding the presence of different CT features (e. g. ground glass opacity, consolidation, crazy paving, vessel enlargement, shape, and margin of opacifications), distribution of lesions in the lung and extent of parenchymal involvement. For subgroup analyses the patients were divided according to the percentage of parenchymal opacification (0-33 %, 34-66 %, 67-100 %) and according to time interval between symptom onset and CT date (0-5 d, 6-10 d, 11-15 d, > 15 d). Differences in CT features and distribution between subgroups were tested using the Mantel-Haenszel Chi Squared for trend. RESULTS: The frequency of CT features (ground glass opacity, consolidation, crazy paving, bronchial dilatation, vessel enlargement, lymphadenopathy, pleural effusion) as well as pattern of parenchymal involvement differed significantly depending on the duration of disease and extent of parenchymal involvement. The early phase of disease was characterized by GGO and to a lesser extent consolidation. The opacifications tended to be round and to some extent with sharp margins and a geographic configuration. The vessels within/around the opacifications were frequently dilated. Later on, the frequency of consolidation and especially crazy paving increased, and the round/geographic shape faded. After day 15, bronchial dilatation occurred, and lymphadenopathy and pleural effusion were seen more frequently than before. CONCLUSION: The prevalence of CT features varied considerably during the course of disease and depending on the severity of parenchymal involvement. Radiologists should take into account the time interval between symptom onset and date of CT and the severity of disease when discussing the likelihood of COVID-19 pneumonia based on CT morphology. KEY POINTS: · The frequency of CT features and pattern of parenchymal involvement vary depending on the duration and extent of COVID-19 pneumonia.. · The early phase is characterized by GGO and consolidation which demonstrate a round shape and at least to some extent have sharp margins and a geographic configuration.. · The frequency of consolidation and especially crazy paving increases during the course of disease.. · Beyond day 15 after symptom onset, bronchial dilatation occurs.. · Radiologists should take into account the duration and severity of disease when considering COVID-19 pneumonia.. CITATION FORMAT: · Schaible J, Meiler S, Poschenrieder F et al. CT Features of COVID-19 Pneumonia Differ Depending on the Severity and Duration of Disease. Fortschr Röntgenstr 2021; 193: 672 - 682.

Sharp margin and geographic shape: systematic evaluation of two novel CT features in COVID-19 pneumonia.

OBJECTIVE: CT is important in the care of patients with COVID-19 pneumonia. However, specificity might be poor in the absence of a clinical and epidemiological context. The goal of this work was to systematically evaluate two novel CT features (sharp margin and geographic shape) of COVID-19 pneumonia. METHODS: All patients with reverse transcription polymerase chain reaction proven COVID-19 pneumonia and chest CT between March first and April 15, 2020 were retrospectively identified from two tertiary care hospitals in Germany. The CTs were evaluated regarding the presence of typical CT signs (e.g. ground glass opacitiy, consolidation, crazy paving). Moreover, the shape of the opacifications (round, geographic, curvilinear) and their margin (unsharp, sharp) was determined. RESULTS: The study population comprised 108 patients (64 male) with a mean age of 59.6 years. Ground glass opacities (96%) and consolidation (75%) were the most prevalent CT signs. Crazy paving was seen in 17%, bronchial dilatation in 21%, air bronchogram in 29%, vessel enlargement in 47%, cavitation in 0%, lymphadenopathy in 32%, pleural effusion in 16%. Round configuration of densities was present in 41% of CTs, geographic shape in 27% and curvilinear opacities in 44%. 79% of opacifications were at least partially sharply marginated. In almost all cases, the lung was affected bilaterally (94%). CONCLUSION: The CT pattern of COVID-19 pneumonia in a cohort from Germany was in accordance with prior studies. However, we identified two novel CT signs of COVID-19 pneumonia which have so far not been systematically evaluated. A sharp border and geographic shape of opacifications were frequently observed. ADVANCES IN KNOWLEDGE: The newly described CT features "sharp margin" and "geographic shape" of opacifications in patients with COVID-19 pneumonia might help to increase specificity of CT.