MR imaging of unilateral pulmonary artery anomalies.

Magnetic resonance (MR) imaging of the pulmonary arteries was performed in seven children with unilateral pulmonary artery abnormalities. Five had congenital absence or interruption of a pulmonary artery; two had postsurgical occlusion or narrowing of a pulmonary artery. A small patent hilar pulmonary artery was identified in one of the five cases of congenital pulmonary artery interruption or absence. Occluding thrombus was identified in the right pulmonary artery of one child following pulmonary artery banding. In another case marked narrowing of the right pulmonary artery was identified secondary to migration of a pulmonary artery band. The MR findings were confirmed by angiography in all cases. Magnetic resonance appears to be a useful noninvasive modality for accurate anatomic depiction of unilateral pulmonary artery abnormalities in childhood. It may be especially valuable for diagnosis of pulmonary artery stenosis or occlusion following surgical treatment of congenital heart disease.