Bronchial atresia

Imaging description Bronchial atresia is characterized by focal obliteration of a bronchus with normal structures distally [1–3]. Bronchial atresia typically involves the upper lobes with the apicoposterior segment of the left upper lobe being the most common location [2, 3] (Figures 6.1 and 6.2). Bronchial atresia most often affects segmental bronchi, however, lobar or subsegmental bronchi may also be involved (Figure 6.3). Mucus plugging typically forms distal to the stenosis resulting in a branching tubular opacity or bronchocele. There is usually a distinct separation between the mucoid impaction and the hilum. The alveoli distal to the atretic bronchus are ventilated by collateral pathways which results in a region of hyperinflation of the lung distal to the atretic segment which shows air trapping on expiratory imaging. Importance Bronchial atresia is typically an incidental finding that is discovered in the second or third decade of life [2]. Recognition of the characteristic findings of bronchial atresia on imaging should allow vascular anomalies or other causes of pulmonary masses to be excluded.