Study on the Dynamic Changes in Chest CT Findings of COVID-19 Rehabilitated Patients

Objective: To study the dynamic changes in CT findings in COVID-19 (coronavirus disease-19, COVID-19) rehabilitated patients. Methods: A total of 148 chest CT images of 37 patients with COVID-19 were collected. In the first 21 days of the course of disease, 7 stages were performed every 3 days, and the eighth stage was performed after 21 days. Results: In the first chest CT examination, 19 cases were ground glass opacity, and 18 cases were high-density shadows with consolidation. The lesion shape was flaky and patchy in 33 cases. The percentage of consolidation, air bronchogram, fiber cord, interlobular septal thickening, subpleural line and pleural thickening were the highest on days 4-6, 7-9, 7-9, 10-12, 19-21 and 19-21, respectively. The highest percentage of disease progression was 80.00% on days 4-6, and then the percentage of disease progression gradually decreased with the extension of the onset time. The percentage of patients with improvement gradually increased from days 4-6, reaching 83.33% on days 16-18 and 100.00% on day 21. The percentage of lesion range enlargement and density increase was the highest on days 4-6, both of which were 60.00%，Then the percentage of both decreased gradually. The percentage of patients with lesion range reduction and density absorption dilution increased gradually with the onset time. There was no obvious regularity in the number of lesions. Conclusion: Patients with COVID-19 have regular changes in their lung conditions.