The computed tomographic appearances in pulmonary artery atresia.

Isolated pulmonary artery atresia is an uncommon congenital abnormality. Plain radiography and ventilation/perfusion lung scintigraphy may suggest the diagnosis but pulmonary angiography has traditionally been recommended for confirmation. The computed tomographic (CT) appearances of four patients with isolated atresia of a pulmonary artery are described. In each case the atretic segment of the abnormal vessel could be identified. Other CT findings included reduction of volume of the involved hemithorax, increased density of the affected lung, a small hilum, and an abnormal pulmonary vascular pattern thought to be due to the collateral systemic arterial supply to the intrapulmonary branches of the atretic pulmonary artery. The diagnosis of isolated pulmonary artery atresia can be made using dynamic, contrast enhanced CT without recourse to more invasive procedures.