Chronic Pulmonary Sequels on CT Scans of Patients with Covid-19

Background: Lung tissue changes following COVID-19 may persist for a long time after discharge and recovery, but not enough information is available about these chronic pulmonary sequels. We addressed to evaluation of chronic pulmonary sequels on CT scans of patients with COVID-19. Methods: This cross-sectional study was conducted on 94 patients with COVID-19 who were evaluated by CT scan at the time of discharge and also underwent continuous evaluation by CT scan of the lungs for at least three months. Through reviewing the hospital archive files, patients' backgrounds and three-month follow-up information were collected. Results: Chronic pulmonary involvement during the follow-up of patients was found in 83%. Peripheral and diffuse involvements were revealed in 79.8% and 3.2% respectively. Also, single-lobar and multi-lobar involvements were found in 69.1%% and 13.8% respectively. In terms of abnormal lung findings on CT scan, ground-glass opacity was found in 20.2%, Crazy paving pattern in 2.1%, reticulation in 3.2%, parenchymal band in 12.8%, consolidation in 1.1% and bronchiectasis in 3.2%. The mean CT score was also 4.21 ± 3.45. The appearance of findings in CT patients was strongly influenced by the patients 'age, body mass index, underlying comorbidities, and also, the severity of initial COVID-19. Conclusion: Within at least three months of disease recovery in hospitalized patients with COVID-19, evidence of pulmonary involvement in 83% in the form of chronic pulmonary sequels can be expected. The most common findings related to pulmonary involvement included GOO in 20.2% and parenchymal band in 12.8% of cases.