Medium-term Pulmonary CT Findings in COVID-19 Survivors: A Three-month Prospective Follow-up Study

Introduction: The mid-term follow-up of pulmonary computed tomography (CT) radiological features of people who recovered from COVID-19 chest infection is limited. Mediumterm follow-up will create data that assist in structuring a follow-up plan to facilitate drug management in adjusting the course of the disease to prevent long-term lung complications. The study aims to analyze the remaining pulmonary findings three months post-COVID-19 infection recovery. Methods: 80 participants in this prospective study had a history of COVID-19 pneumonia verified by RT-PCR testing and a chest CT scan showing pulmonary involvement during the acute illness. After three months of recuperation (as verified by a negative RT-PCR test), the radiological features of each patient's chest CT scan were gathered, examined, and classified into complete resolution or residual changes. Results: Out of the total 80 patients included in this study, 52 (65%) patients demonstrated a complete radiological resolution, and the remaining 28 (35%) had residual pulmonary CT findings. The predominant residual findings observed in recovered patients were ground-glass opacity (GGO) and fibrous stripes (each 26/28; 92.9%), followed by pulmonary reticular changes (20/28; 71.4%). Patients with residual radiological abnormalities were older than those who had complete radiologic resolution (p = 0.02). In addition, statistical analysis revealed that older age was a significant factor related to the development of residual radiological abnormalities (p = 0.04). Further, the presence of co-morbidities was significantly related to residual radiological findings (p = 0.04). Although smokers showed a higher prevalence of residual abnormalities than non-smokers, the association was not statistically significant (p = 0.06). Discussion: Patients with persistent abnormalities tended to be older and had more comorbidities, which are statistically significant factors. The radiological patterns of COVID-19 infection significantly changed over time, that’s the GGO and unconventional paving appearance predominating in the first few days and after 28 days of the infection, but tend to regress later on. According to this study, the majority of CT scan residual finding patterns were subpleural, diffuse, and random, which results in line with previous studies. Conclusion: At the three-month follow-up, the rate of full lung recovery on chest CT scans was considerably greater for patients under 40 than for those over 40. Personalized follow-up strategies can be guided by medium-term imaging, particularly for patients who are elderly or have serious illnesses.