An Observational Study on Unique High Resolution Computed Tomography Pattern of Post-COVID Pulmonary Fibrosis

Background: As the severe acute respiratory syndrome coronavirus 2 era commenced, a new entity was added to the already hefty bulk of parenchymal lung diseases in post-COVID-19 pulmonary fibrosis. A wide range of findings from mild ground glass opacities to exuberant fibrosis are seen on high resolution CT of the thorax. However, the authors came across a pattern that was frequently repeated, and therefore conducted an observational study on the radiological findings. Method: The study was conducted for a period of 6 months in the departments of Respiratory Medicine and Radiodiagnosis at King George’s Medical University, Lucknow, India. The radiological findings on high resolution CT thorax of consecutive patients who reported to the Department of Respiratory Medicine after recovering from COVID-19, and were previously reverse transcriptase-PCR-positive or serologically confirmed, were studied. Result: There were a total of 56 subjects (32 males; mean age: 56 years). The most common finding was ground glass opacities (89%). Reticulations were seen in 86% of patients, with a unique dome-shaped fibrosis parallel to pleural surface in 54%, patchy consolidation in 49%, and scattered cysts in 43%. The distribution was mostly bilateral with slight predominance of lower lobes (57%). Conclusion: Ground glass opacities, reticulations, and consolidation are fairly common in patients with pulmonary sequelae of COVID-19. It has a peculiar predilection for involvement of subpleural space with cupola or band-shaped fibrosis.