Computed Tomography Evaluation of Airway Changes in Adult Patients with COVID-19 Pneumonia

Objective: To investigate airway abnormalities on chest CT in adult patients with COVID-19 pneumonia. Study Design: Observational study. Place and Duration of Study: Department of Radiology, Affiliated Hospital of Jining Medical University, Jining, Shandong, China, from January to April, 2020. Methodology: CT scan images were analysed retrospectively. The main CT findings, including pulmonary opacities, airway wall visibility, wall thickening, luminal changes, and the formation of mucus plugs were evaluated. Airway segments were classified into three types based on the spatial relationship between conducting airways and pulmonary opacities. Results: A total of 275 lesions were detected in 52 patients. Of these, 170 (61.82%) lesions were associated with 243 airway segments, including segments enclosed within lesions (type I, 152, 62.55%), crossing the lesions (type II, 51, 20.99%), and abutting the lesions (type III, 40, 16.46%). The bronchial walls of 154 (63.37%) segments were ill-defined; whereas, the walls of 89 (36.63%) segments were well-defined; in the latter group, 62 (69.66%) showed mild thickening. The bronchial lumen of 183 (75.31%) segments presented mild bronchiectasis and 60 (24.69%) segments appeared normal. Mucus plug was detected in one segment (0.41%). There were no cases of bronchial stenosis, and all bronchial segments located in normal lung regions appeared normal. The appearance of 196 (80.66%) affected bronchi was completely restored before hospital discharge. Conclusion: Typical airway changes in adult COVID-19 pneumonia include bronchial wall thickening without significant stenosis of the airway lumen and the absence of bronchial mucus plugs. Moreover, bronchi located in unaffected lung regions have a normal appearance. These characteristics have potential value in differential diagnosis.