螺旋CT对亚段以上肺栓塞的诊断价值

Evaluation of Spiral CT in Diagnosing Sub-segmental or More Proximal Pulmonary Embolism

目的 评价螺旋CT在诊断亚段以上肺栓塞 (PE)中的价值。资料与方法 对 2 5例因临床高度疑诊PE而行螺旋CT肺动脉造影的患者 ,回顾分析其螺旋CT肺动脉造影的影像学表现 ,并进行统计学分析。结果 螺旋CT肺动脉造影对亚段肺动脉的显示率达 76 .8% ,检出PE阳性 2 0例 ,阴性 5例 ,其中真阳性 19例 ,假阳性 1例 ,真阴性 3例 ,假阴性 2例。直接征象包括血管腔完全闭塞、部分充盈缺损、轨道征和附壁血栓 ;间接征象有局部肺纹理稀疏纤细、右室增大或肺动脉扩张、“马赛克”征、胸腔积液或心包积液、肺梗死灶。螺旋CT诊断亚段以上PE的敏感性为 90 .5 % ,特异性为 75 .0 % ,准确性为 88.0 % ,阳性预测值为 95 .0 % ,阴性预测值为 6 0 .0 %。结论 螺旋CT诊断PE简便、安全、准确性高 ,是诊断亚段以上PE的一种可靠方法。

Objective To evaluate spiral CT in the diagnosis of sub-segmental or more proximal pulmonary embolism (PE). Materials and Methods Spiral CT pulmonary angiography (SCTPA) was performed in 25 cases with highly-suspected PE. CT findings were retrospectively analyzed.Results The dysplaying rate of SCTPA for sub-segmental arteries was 76.8%. PE was demonstrated in 20 cases, of which 11 were true positive and one was false positive. Normal finding was seen in 5 cases, of which 3 were true negative and two false negative. Direct signs of PE included complete occlusion of the arteries, partial filling defect, track sign and mural thrombus. The indirect signs included localized reduced lung markings, right ventricular enlargement, dilated pulmonary artery, “mosaic” sign, pleural or pericardial effusion and lung infarction. The sensitivity, specificity and accuracy of SCTPA in diagnosing PE was 90.5%, 75.0% and 88.0%, respectively, with the positive predictive value being 95.0% and the negative predictive value 60.0%.Conclusion SCTPA is an effective, simple and safe technique for the diagnosis of PE. It is a reliable means in detecting sub-segmental or more proximal PE.