异常体动脉供应正常左下肺基底段的胸部X线片和螺旋CT表现

目的 总结异常体动脉供应正常左下肺基底段在胸部X线片和螺旋CT上的特征性表现。方法 回顾分析5例异常体动脉供应正常左下肺基底段的胸部X线片和螺旋CT资料。结果 5例异常体动脉供应正常左下肺基底段在胸部X线片上均表现为心后区肿块，左下肺动脉纹理细小，受累左下肺区域无正常肺动脉分支影分布，但有异常增粗纹理。CT上5例均表现为受累肺组织体积轻度缩小，支气管通畅，2例肺实质呈磨玻璃状改变。5例均可见左下肺动脉在背段动脉起始远侧缺如，增粗扭曲的异常体动脉起自降主动脉，其扩张的分支分布于受累肺段。1例血管造影表现与CT相仿。结论 该病在胸部X线片上的表现有一定特征性。增强螺旋CT扫描可明确诊断，以避免创伤性的血管造影和致命的穿刺活检。

Anomalous systemic arterial supply to normal basal segments of the left lower lobe of the lung: characteristic findings on chest radiography and spiral CT

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.