Relational analysisof the COVID-19chest CT betweentime period and lung image changes

• 1、Department of Infectious Diseases, Ezhou Central Hospital（Fankou District）, Ezhou 436001,China

Abstract：\Objective The COVID-19（Corona Virus Disease 2019） patients were observed to observe the changes of chest CT lung images in different time periods, so as to research on the relationship between lung imaging changes and chest CT time period in patients.. Methods The COVID-19 patients 94 cases were retrospectively analyzed in one week (1~7 days), two weeks (8~14 days), two weeks later (>14 days) three time periods. The chest CT image changes of the three time periods were compared. The COVID-19 patients were divided into general and severe groups. Firstly, using the chest CT lung lesions of the patients pre-hospital as a reference, The changes of chest imaging lesions in each time period after admission and the changes of chest CT lung lesions in each time period were compared. Results Comparing 94 cases of COVID-19 patients with chest CT in each time period after admission and chest imaging before admission, there were significant differences in chest CT changes between the normal group and the severe group within one week and two weeks (P<0.05). In one week, the improvement rate was 27.6% (16/58) in the general group and 16.6% (6/36) in the severe group , OR = 1.90.In two weeks, the improvement rate was 93.1% (54/58) in general group and 50.0% (18/36) in severe group, OR = 13.50. The comparison of chest CT images in each time period before and after admission showed that the CT changes of normal and severe chest within one week and two weeks later were P<0.05, and the difference was statistically significant. During one week, the improvement rate was 27.6% (16/58) in the general group and 16.6% (6/36) in the severe group ,OR = 1.90. Two weeks later, the improvement rate of the general group was 10.3% (6/58), the improvement rate of the severe group was 88.9% (32/36), OR = 0.01. Conclusion The COVID-19 Patients in a week, the absorption time of lung lesions was fast for general type , after 2 weeks treatment the lung lesions absorption obviously for severe type, during the treatment of COVID-19, dynamic images of chest CT were used to observe the changes of lung lesions. So early assessment of therapeutic effect, early intervention, and then reduce the risk of death.

Keywords： SARS-CoV-2；COVID-19；Chest CT；Time period Image changes