【摘要】 目的:探讨肺栓塞前、后螺旋CT(HCT)平扫双侧肺实质的CT值变化情况。材料和方法:8只犬于DSA下经导管注入直径2～4mm、长1cm的明胶海绵条后,复制为单侧外围性肺栓塞的动物模型。分别于栓塞前及栓塞后1h、3d、7d、14d进行HCT平扫。首先根据DSA发现的栓塞肺动脉的位置,在不同时间的HCT平扫图像上,分别测量栓塞区与非栓塞区的CT值,比较其有无显著性差异。其次分别选取12个相同的层面。通过画感兴趣区的方法,测量双肺前、中、后肺野的CT值,比较栓塞前和栓塞后不同时间CT值的差异。结果:肺栓塞前与栓塞后1h～14d,栓塞区肺野与非栓塞区肺野的CT值无显著性差异(P>0.05)。肺栓塞后3～14d,双肺的CT值弥漫性低于栓塞前的CT值,两者有显著性差异(P<0.01),而肺栓塞后1h的CT值与栓塞前比较无显著性差异(P>0.05)。结论:外围性肺栓塞后引起的广泛性支气管痉挛和小动脉收缩,肺内气体潴留是双侧肺野CT值降低的主要原因,而栓塞区与非栓塞区之间无明显的密度差异。更多还原

【Abstract】 Purpose: To investigate the change of CT values on plain HCT scans before and after pulmonary embolism (PE) . Materials and Methods: 8 dogs were made PE animal models by introducing gelatin sponge of 2 ~ 4mm in diameter and 1cm long into unilateral pulmonary arteries through a catheter under DSA. Plain HCT scans were done before PE and 1 hour, 3 days, 7 days, 14 days after PE. First according to the location of the embolic arteries observed on DSA, measure the CT values of the embolic areas and the counter - lateral normal pulmonary parenchyma. Then regions of interest of the anterior, middle and posterior pulmonary areas were drawn respectively on 12 identical sections of the above plain HCT scans, then the CT values were measured and compared statistically. Results: The CT values of the embolic areas and the normal pulmonary parenchyma had no statistical difference before and after PE(P > 0.05). The CT values of 3 days, 7 days and 14 days after PE were diffusely lower than the CT values of pre - PE(.P < 0.01), and the CT values of 1 hour after PE were similar with which of pre - PE(P > 0.05) .Conclusion: Because of the spasm of airway and the contraction of small pulmonary arteries, the CT values on plain HCT scans after PE decreased diffusely, while the embolic and normal pulmonary parenchyma had no statistical difference.更多还原