[Two cases of intralobar pulmonary sequestration--demonstration of the aberrant artery by magnetic resonance imaging].

Diagnosis of intralobar pulmonary sequestration has required demonstration of systemic blood supply by arteriography. We report two cases in which retrocardiac abnormal shadows were observed on chest radiographs and aberrant arteries arising from the descending aorta toward the sequestrum were demonstrated by magnetic resonance imaging (MRI). The sequestra were observed as high intensity area suggesting cystic lesions on T2-weighted MRI. In both cases, the sequestra were excised and aberrant arteries (5 mm and 10 mm in diameter) arising from the aorta were recognized at surgery. Both cases were diagnosed as intralobar sequestrations histopathologically. MRI is a safe noninvasive alternative for diagnosis of pulmonary sequestration instead of arteriography in some cases with a larger aberrant artery.