Objective: To quantitatively evaluate the quality of advanced modeled iterative reconstruction (ADMIRE) combined with 70 kVp and linear blending images in low dose dual energy (70 kVp/sn150 kVp) pulmonary angiography. Methods: A total of 74 cases with normal BMI underwent dual-source CT dual-energy pulmonary angiography with small amount of contrast medium (30 ml) from 2015 to 2017 from the First Affiliated Hospital of Zhengzhou University were randomly assigned to protocol Ⅰ(100 kVp/sn140 kVp) or protocol Ⅱ(70 kVp/sn150 kVp). 70 kVp+ ADMIRE (group 1), linear blending+ ADMIRE (group 2), 100 kVp+ SAFIRE (group 3) images were obtained. CT value and noise standard deviation (SD) of pulmonary arteries were measured in pulmonary trunk artery, left pulmonary artery and left superior pulmonary artery, then SNR and CNR were calculated. Radiation dose parameters (CTDIvol, DLP) were recorded. Results: CT values of pulmonary artery of group 1 were significantly higher than those in group 2 and 3 (both P<0.05). In group 2, SD value of pulmonary artery was lower than that of group 1 and 3(both P<0.05). SD value of pulmonary trunk and left pulmonary artery in group 1 was higher than that in group 3 (P<0.05), SD value of left superior pulmonary artery had no significant difference between group 1 and group 3 (P>0.05). SNR and CNR value in group 1 and group 2 had no statistical difference, but they were both higher than that in group 3 (both P<0.05). The effective dose of protocolⅠwas 46% lower than protocol Ⅱ. Conclusion: ADMIRE combined with 70 kVp and linear blending images are better than SAFIRE combined with 100 kVp images, and radiation dose is reduced.70 kVp/sn150 kVp with small amount of contrast medium (30 ml) is a feasible dual energy pulmonary artery scanning protocol.
目的： 定量评价低剂量双能量(70 kVp/sn150 kVp)肺动脉成像中高级模拟迭代重建(ADMIRE)联合70 kVp、线性融合图像的质量。 方法： 收集2015—2017年郑州大学第一附属医院行双源CT双能量肺动脉成像的体质指数正常患者共74例，随机平均分为两组，一组为70 kVp/sn150 kVp扫描模式，一组为100 kVp/sn140 kVp扫描模式，对比剂用量均为30 ml。比较70 kVp＋ADMIRE(组1)、线性融合＋ADMIRE(组2)、100 kVp＋SAFIRE(组3)肺动脉干、左肺动脉干、左肺上叶动脉的CT值、SD值、SNR、CNR值及辐射剂量参数CT容积剂量指数、剂量长度乘积，并进行统计学分析。 结果： 组1肺动脉CT值显著高于组2和组3(均P<0.05)。组2肺动脉SD值低于组1和组3(均P<0.05)。肺动脉干及左肺动脉干SD值组1高于组3(P<0.05)，而叶动脉SD值组1与组3间差异无统计学意义(P>0.05)。肺动脉SNR、CNR值组1与组2间差异无统计学意义，但均高于组3(均P<0.05)。有效剂量较100 kVp/sn140 kVp组降低了46%。 结论： ADMIRE联合70 kVp、线性融合图像质量优于100 kVp联合SAFIRE图像，且辐射剂量降低，是一种可行的双能量肺动脉扫描模式。.
Keywords: Angiography; Pulmonary artery; Tomography, X-ray computed.