中文摘要：

目的：评价肺灌注成像技术（Lung PBV）与肺动脉栓塞程度的相关性。方法收集165例临床疑诊肺栓塞（PE）并行双源 CT（DSCT）Lung PBV 检查的患者。2位医师分析所有患者的 Lung PBV 图像,按肺段记录灌注减低和（或）灌注缺损的部位。2个月后,另外2位医师再随机分析所有患者的 CTPA 图像,按肺段记录栓塞部位及栓塞程度。结果165例患者最终诊断为 PE 者41例,共有164支肺段动脉栓塞,其中肺动脉部分栓塞56支,完全栓塞108支,Lung PBV 中141个肺段显示灌注缺损,部分性栓塞肺段显示灌注缺损42个,完全性栓塞肺段出现灌注缺损99个。17个肺段 Lung PBV 可见灌注异常,CTPA 图像上相应肺动脉中未见明确栓子,误诊原因包括肺气肿、肺大疱,炎性渗出、实变、肺不张,支气管扩张及大血管硬化束伪影。23个肺段（9个肺段为完全性栓塞,14个肺段为部分性栓塞）CTPA 图像可见肺动脉内的栓子,Lung PBV 未发现灌注异常,漏诊原因有：栓塞程度、栓塞肺动脉直径、肺气肿及 PE 病程。Lung PBV 与 CTPA 呈中等到显著相关（Lung PBV 与部分性肺动脉栓塞呈中等相关 r=0.508,P =0.022；与完全性肺动脉栓塞显著相关 r=0.905,P =0.000）。结论双能量 Lung PBV 能较准确地发现 PE 所致的灌注异常,Lung PBV 图像结合 CTPA 图像综合分析,可全面评价 PE 后肺血流灌注分布。

英文摘要：

Objective To evaluate the correlation between CT perfusion blood volume （Lung PBV）and the degree of pulmonary embolism by CT pulmonary angiography （CTPA）.Methods 1 65 patients with suspected pulmonary embolism underwent dual-ener-gy CT angiography,then the Lung PBV iodine distribution was analyzed by using a software algorithm.Consistent CTPA results evaluated by two experienced radiologists were taken as standard reference.After two months,the CTPA images were assessed by other two radiologists at random.The position and the number of perfusion defects,and （or）hypoperfusion were recorded.Results Of all 1 65 suspected patients,41 were diagnosed as pulmonary embolism with involved 1 64 segment arteries including part occlusion in 56 and complete occlusion in 108.Lung PBV showed perfusion defect in 141 pulmonary segment including 42 in patients with part occlusion and 99 in ones with complete occlusion.1 7 pulmonary segments were misdiagnosed with part occlusion in 9 and complete ones in 8.23 segments were misdiagnosed including part occlusion in 14 and complete ones in 9.The perfusion defect of Lung PBV was correlated to CTPA moderately or well （to part occlusion with r =0.508 and P =0.022;to complete ones with r =0.905 and P =0.000）.Conclusion Dual-energy lung perfusion imaging is helpful for accurate assessment of abnormal blood flow distribution caused by pulmonary embolism,and improve the diagnosis.