Computed tomography chest findings in hospitalised COVID-19 patients presenting with pulmonary complications

Background: Since COVID-19 became a global pandemic in 2020, Computed tomography (CT) chest and CT pulmonary angiography (CTPA) have been identified to be highly sensitive for identifying pulmonary features and complications. Objectives: The study aimed to describe the typical imaging findings on CT chest imaging and the prevalence of pulmonary embolism in COVID-19 patients across three infection periods, each with a dominant virus strain, Beta, Delta, and Omicron variants. Methods: A retrospective review of CT chest and CTPA images for adult patients imaged from October 2020 to March 2022 at three university-affiliated hospitals in Johannesburg was undertaken. Results: A total of 307 chest CT scans were reviewed during the study period. The typical imaging findings were ground glass opacities (77%), patchy, peripheral distribution (59%), and septal thickening (59%). Consolidation, pleural effusion, and fibrosis were less frequently visualised. The overall prevalence of pulmonary embolism was 32%. There was no significant statistical difference in the observed imaging features during the three virus strain phases of the epidemic. Fewer imaging studies were done during the Omicron phase, which is attributable to the milder clinical profile of the variant. Conclusion: The typical imaging pattern for patients with COVID-19 was peripheral, patchy ground glass opacities with interlobar septal thickening. Fibrotic banding and bronchiectasis were also frequently noted, especially when imaged late. Pulmonary embolism was found in almost a third of patients. No differences in imaging patterns were found during the various phases of the COVID-19 epidemic.