Congenital Bronchial Atresia Mimicking Pulmonary Sequestration in the Lower Lobe: A Case Report

Congenital bronchial atresia (CBA) is a rare airway anomaly that may radiologically resemble other congenital pulmonary lesions, particularly when it occurs in the lower lobes. A 41-year-old woman was referred for surgical treatment of suspected pulmonary sequestration based on imaging findings. Computed tomography (CT) at the referring hospital showed a cavitary lesion with fluid retention in Segment 7 (S7) of the right lower lobe, with surrounding ground-glass opacity, suggesting infection associated with pulmonary sequestration. Re-evaluation at our institution identified the lesion as a bronchocele with focal hyperinflation, interruption of the segmental bronchus (B7), and a normally distributed pulmonary artery (A7) without aberrant systemic supply. Three-dimensional CT clearly demonstrated these bronchovascular features and supported the diagnosis of CBA. Thoracoscopic right lower lobectomy was performed, and histopathological findings confirmed the diagnosis of CBA. This case highlights the importance of systematic evaluation of bronchial continuity and vascular supply in congenital lower-lobe lesions, for which three-dimensional CT reconstruction may be useful.