ABSTRACT
Objective To summarize the characteristic findings on chest radiography and spiral CT of anomalous systemic arterial supply to normal basal segments of the left lower lobe of the lung.Methods Five patients with anomalous systemic arterial supply to normal basal segments of the left lower lobe of the lung were retrospectively reviewed.Chest radiography,and contrast-enhanced spiral CT scan were analyzed. Results On posteroanterior chest radiographs,the findings in 5 cases of this anomaly were all shown as a retrocardiac mass,narrowing lower lobar pulmonary artery shadow,and without normal lower lobar pulmonary artery branches but there were dilated abnormal markings in left lower lung zone.On contrast- enhanced spiral CT scans,the involved left lower lobe of the lung had mild volume loss but normal bronchial trees in all 5 cases and areas of ground-glass opacity in 2 cases.The absence of normal left lower lobar pulmonary artery distal to the origin of superior segmental artery,anomalous systemic artery originating from the descending aorta,diffuse dilatation of the systemic arterial branches distributed in the basal segments of the left lower lobe were also found in all the patients.One patient who underwent angiography had similar vessel features with spiral CT.Conclusion There are some characteristic findings on chest radiography in this anomaly.the contrast-enhanced spiral CT scans are important in diagnosing and avoiding invasive angiography and life-threatening lung biopsy.