基于定量 CT 对新型冠状病毒肺炎肺部改变的纵向研究

Objective To investigate the changes in CT quantitative parameters because of the lung changes induced by 2019 novel coronavirus (COVID-19) for providing quantitative imaging basis for patients with COVID-19. Methods A retrospective analysis of 17 patients with confirmed COVID-19 was carried out. The initial and follow-up chest CT images were analyzed quantitatively. The quantitative CT indexes included total lung volume (TV), total lesion volume (TLV), the percentage of lesion volume in total lung volume (TLV/T%), the highest lesion density region (HLD), the lowest lesion density region (LLD), percentage of ground glass opacity (GGO%). Results A total of 42 chest CT scans were conducted in 17 patients with confirmed COVID-19, and the average interval was (4±1) days. According to the time of onset, the course of disease was divided into 4 stages, namely day 0-3 (stage 1), day 4-7 (stage 2), day 8-14 (stage 3) and day 15-21 (stage 4). TLV and TLV/TL% reached the highest in stage 2 (day 4-7) and stage 3 (day 8-14), while TV and GGO% were the lowest (P=0.001). The fastest progression of TLV/TL% was found in stage 2 (day 4-7). Patients with rapid disease progression (with more than 50% TLV progression in 2 follow-up CT scans) had the characteristics of elder age (P<0.05), decreased lymphocyte count (P<0.001), and lower GGO% but higher TLV/TL% in the first CT scan (P<0.05). Conclusion Chest quantitative CT related indicators suggest that the fastest disease progression is on day 4-7. The patients with elder age, low leukocyte count, large lesion volume and high lesion density in initial CT are more likely to have rapid disease progression.