Relationship between initial CT signs and symptoms onset time in COVID-19 patients outside Wuhan

ABSTRACT

Objective: To explore the correlation between initial chest CT signs and onset time in patients with coronavirus disease 2019 (COVID-19) outside Wuhan area and to identify the early changes in chest CT signs. Methods: We made a retrospective analysis of the clinical features and CT signs of confirmed cases of COVID-19 in Shaanxi Province from January 22 to February 10, 2020. The CT signs were mainly analyzed for ground glass opacities (GGO), consolidation and GGO combined with consolidation in the lung, and the degree of lung injury in each patient was scored at the same time. The correlation of CT signs and lung injury score with onset time was analyzed, and the data were non-linearly fitted (quadratic fitting curve) to judge the changes of CT signs and scores with time. Results: A total of 293 lesions were detected in 91 patients with COVID-19, including 143 (48.8%) GGO, 116 (39.6%) GGO with consolidation and 34 (11.6%) simple consolidation. The nonlinear fitting analysis revealed that the GGO had a downward trend with the onset time, the quadratic fitting curve of GGO combined with consolidation showed a positive "U" shape, and the solid change showed an inverted "U" shape;and the three signs had a turning point on the 7th day. At the same time, the lung injury score of the patients peaked on the 7th day. Conclusion: The main CT manifestations of patients with COVID-19 are GGO and GGO combined with consolidation, and the 7th day of onset may be the key time point for the change of CT signs. © 2020, Editorial Board of Journal of Xi'an Jiaotong University (Medical Sciences). All right reserved.