目的 探讨采用西门子双源128排螺旋CT诊断结缔组织病肺间质病变致肺动脉高压的价值。方法 选取60例于2013年1 月至2015年5月期间我院接收的结缔组织病伴有肺动脉高压(PAH)的患者，对60例PAH患者及42例肺动脉压力正常者 进行肺动脉CTA检查，分析测量结果。结果 PAH组中55例可见主肺动脉扩张，CT诊断PAH的准确性86.67%(52/60)， 主肺动脉直径(MPAD)、升主动脉直径除以主肺动脉直径值(rPA)、主肺动脉直径除以降主动脉直径值(rPD)值均高 于对照组(P<0.05)；PAH组MPAD、右肺动脉直径(RPAD)、左肺动脉直径(LPAD)、右下肺动脉直径(RLLPAD)明显高于 对照组(P<0.05)；主肺动脉直径≥2.9cm诊断的特异性、敏感性、阴性预测值、阳性预测值分别为85.5%、87.6%、 87.4%、85.4%。结论 多层螺旋CT具有较高的空间分辨力，获得的肺动脉CT图像较为清晰，能准确的诊断PAH，具有 推广价值。

Objective To investigate the application value of dual source 128 slice spiral CT in the diagnosis of pulmonary artery hypertension which caused by interstitial lung disease of connective tissue disease. Methods A total of 60 cases of connective tissue disease with pulmonary artery hypertension from January 2013 to May 2015 in our hospital were rolled into the study. 60 PAH patients and 42 cases of normal cases accepted pulmonary CT angiography examination, and the results were analyzed. Results 55 cases showed the expansion of the main pulmonary artery in the PAH group, the accuracy of CT diagnosis is 86.67% (52/60), MPAD, rPA, rPD values were higher than the control group (P<0.05). The diameter of main pulmonary artery (MPAD), right pulmonary artery(RPAD), left pulmonary artery(LPAD), right inferior pulmonary artery (RLLPAD) of PAH group was significantly higher than the control group (P<0.05). The specificity, sensitivity, negative value and positive predictive value of the main pulmonary artery diameter over 2.9 cm predicted that were 85.5%, 87.6%, 87.4%, 85.4%. Conclusion Multi slice spiral CT has high spatial resolution, and gets the high quality CT images of the pulmonary artery which helps the diagnosis of PAH, and deverse spreading.