Bronchial atresia is a developmental anomaly characterised by focal obliteration of the proximal segment of a bronchus. It is typically at the segmental or subsegmental level and most commonly occurs in the upper lobes. The bronchi distal to the atresia become filled with mucus and may form a mucocoele. The lung distal to the atretic bronchus develops normally but is overinflated due to collateral air drift with air trapping. Bronchial atresia is usually asymptomatic, as with this case found incidentally on the CT chest of a trauma patient. If symptomatic, it may cause shortness of breath, cough or rarely infection.
Reference: Berrocal T et al, Congenital Anomalies of the Tracheobronchial Tree, Lung, and Mediastinum: Embryology, Radiology, and Pathology, Radiographics 2003;24:e17
Credit: Dr Donna D’Souza