Bronchial atresia with corresponding segmental pulmonary emphysema.

This paper presents a 13-year-old boy suffering from congenital bronchial atresia of the anterior and apicoposterior segments of the left upper lobe with corresponding emphysema, and emphysema with bronchial atresia in the anterobasal segment of the left lower lobe. The aetiology of congenital localized emphysema is not always clear. In the group with a demonstrable check-valve mechanism, which permits air to enter but not to leave the lung, there is either internal stenosis or external compression of the bronchus. The condition is called idiopathic if no cause can be identified, but in some of these cases microscopical examination has disclosed alveolar fibrosis which prevents the rigid alveoli from collapsing on expiration. In these cases the check-valve mechanism exists at an alveolar level. In the small group of rare cases of bronchial atresia, air which enters through a collateral ventilation cannot be expired by the same route, and in these cases there is likewise a check-valve mechanism at an alveolar level; this is associated wiith the occurrence of localized emphysema, characterized by the presence of normal bronchial ramifications which arise from a bronchial sac with a blind proximal ending. The bronchial atresia is believed to occur after the 15th week of intrauterine life, probably as a result of vascular insufficiency. A preoperative diagnosis is possible on the basis of a plain chest radiograph, which shows the localized emphysema as well as an abnormal hilus shadow representing the mucus-filled blind bronchial stump; the diagnosis can be established also by a bronchogram, which shows a filling defect in the affected part of the lung. Surgical treatment is indicated.