Objective. To investigate the predictive factors of residual pulmonary opacity on midterm follow-up CT scans in patients hospitalized with COVID-19 pneumonia. Materials and Methods. This prospective study was conducted in a tertiary referral university hospital in Iran, from March 2020 to December 2020. Patients hospitalized due to novel coronavirus pneumonia with bilateral pulmonary involvement in the first CT scan were included and underwent an 8-week follow-up CT scan. Pulmonary involvement (PI) severity was assessed using a 25-scale semiquantitative scoring system. Density of opacities was recorded using the Hounsfield unit (HU). Results. The chest CT scans of 50 participants (mean age = 54.4 ± 14.2 years, 72% male) were reviewed, among whom 8 (16%) had residual findings on follow-up CT scans. The most common residual findings were faint ground-glass opacities (GGOs) (14%); fibrotic-like changes were observed in 2 (4%) patients. Demographic findings, underlying disease, and laboratory findings did not show significant association with remaining pulmonary opacities. The total PI score was significantly higher in participants with remaining parenchymal involvement (14.5 ± 6.5 versus 10.2 ± 3.7; ). On admission, the HU of patients with remaining opacities was significantly higher (−239.8 ± 107.6 versus −344.0 ± 157.4; ). Remaining pulmonary findings were more frequently detected in patients who had received antivirals, steroid pulse, or IVIG treatments (, 0.02, and 0.001, respectively). Only the PI score remained statistically significant in multivariate logistic regression with 88.1% accuracy (OR = 1.2 [1.01–1.53]; ). Conclusion. Pulmonary opacities are more likely to persist in midterm follow-up CT scans in patients with severe initial pulmonary involvement.

中文翻译：

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COVID-19 严重初始肺部受累患者的随访 CT 扫描评估

目标。调查 COVID-19 肺炎住院患者中期随访 CT 扫描残余肺部混浊的预测因素。材料和方法。这项前瞻性研究于 2020 年 3 月至 2020 年 12 月在伊朗的一家三级转诊大学医院进行。因新型冠状病毒肺炎住院且首次 CT 扫描双肺受累的患者被纳入，并接受为期 8 周的随访 CT 扫描. 使用 25 级半定量评分系统评估肺受累 (PI) 严重程度。使用亨斯菲尔德单位 (HU) 记录混浊密度。结果. 对 50 名参与者（平均年龄 = 54.4 ± 14.2 岁，72% 为男性）的胸部 CT 扫描进行了审查，其中 8 名 (16%) 在随访 CT 扫描中有残留发现。最常见的残余发现是微弱的毛玻璃样混浊 (GGO) (14%)；在 2 名 (4%) 患者中观察到纤维化样变化。人口统计结果、基础疾病和实验室检查结果未显示与剩余肺部混浊显着相关。剩余实质受累的参与者的总 PI 评分显着更高（14.5 ± 6.5 对比 10.2 ± 3.7；). 入院时，仍有混浊的患者的 HU 显着更高（-239.8 ± 107.6 对 -344.0 ± 157.4；). 在接受过抗病毒药物、类固醇脉冲或 IVIG 治疗的患者中，更常发现剩余的肺部发现（、 0.02 和 0.001）。只有 PI 评分在多变量逻辑回归中保持统计学显着性，准确率为 88.1%（OR = 1.2 [1.01–1.53]；). 结论。对于初始肺部严重受累的患者，肺部混浊更有可能在中期随访 CT 扫描中持续存在。