Chest Computed Tomography Imaging Features of Novel Coronavirus Omicron Strain Infection in Children

Objective: To investigate the chest computed tomography (CT) imaging features of novel coronavirus omicron strain infection in children. Methods: The chest CT imaging of 77 children diagnosed with coronavirus disease (COVID-19) using nucleic acid testing or antigen testing from December 10 to 31, 2022 at Shenzhen Children's Hospital were retrospectively analyzed, including 51 males and 26 females. Among them, 50 cases were positive for CT presentation, and their ages ranged from 1 month to 14 years, with a mean age of 5.5 years and a median age of 3.9 years, including 21 cases in the infant and toddler group (≤3 years), 14 in the preschool group (3~7 years), and 15 cases in the school-age group (≥7 years). Two radiologists independently identified the location of intrapulmonary lesions, CT manifestations of intrapulmonary lesions, concomitant CT manifestations of the lungs, extent of lesion involvement, and imaging staging. Results: 50 patients (64.9%) had positive lung CT presentation, with the most lesions in the lower lobes and subpleural areas of both lungs and the least lesions in the hilus of lung, and the number of lesions were single, multiple, and diffusely distributed, with diffuse distribution being the most common. Ground-glass opacity were seen in 16 cases (32%), solid nodules in 20 (40%), lamellar consolidation in 24 (48%), lamellar ground glass in 30 (60%), and solid and ground glass in 20 (40%), with lamellar ground glass being the most common; crazy-paving pattern in 4 cases (8%), thickening of lobular septa in 12 (24%), tree fog sign in 12 (24%), and vascular enlargement in 13 (26%). 7 cases (14%) were of subpleural curvilinear line, 6 (12%) of reversed halo sign, and 17 (34%) of air bronchogram, all without cavitation; 5 (10%) were of pleural effusion, 7 (14%) of pleural thickening, 1 (2%) of pericardial effusion, and 7 (14%) of lymphadenopathy. 29 patients (37.7%) were in the early stage of imaging, 15 (19.5%) were in the progressive stage, and 6 (7.8%) were in the severe stage. Conclusion: The chest CT imaging of novel coronavirus omicron strain infection in children was morphologically diverse. The presence of pleural effusion, pleural thickening, and pericardial effusion suggests a higher risk of serious prognosis. Chest CT in children with omicron strain infection can provide valuable information for diagnosis and determine the extent of the disease.