【摘要】 目的:探讨256层CT显示支气管动脉较佳的扫描参数。方法:依据注射条件的不同,将80例行支气管动脉CT血管成像(CTA)检查的患者随机分成4组,第1、2、3组分别采用4、5、6 ml/s的对比剂注射速率,均采用阈值触发技术扫描,触发阈值均设为300 HU,对比剂总量采用1.5 ml/kg体重。第4组采用6 ml/s注射速率,触发阈值设为120 HU,对比剂总量采用1.0ml/kg体重。扫描结束后,测量各组患者肺动脉、上腔静脉、主动脉及支气管动脉增强扫描增加的CT值,并统计各组支气管动脉显示的优良率。结果:各组肺动脉和上腔静脉增强后增加的CT值间均无统计学差异。增强扫描后主动脉增加的CT值在第4组和1、2、3组之间均有统计学差异;支气管动脉增加CT值在第4组和第1、2组间均有统计学差异,其余组间均无统计学差异。1～4组支气管动脉显示的优良率分别为:50%、55%、65%和80%。结论:采用6 ml/s注射速率、120 HU的触发阈值、1.0ml/kg体重对比剂总量及高浓度对比剂(350mgI/ml),利用MPR、MIP和VR技术是支气管动脉CTA较理想的条件。更多还原

【Abstract】 Objective:Comparison of different scanning and injection protocols for bronchial artery CT angiography(CTA).Methods:Eighty cases scheduled for bronchial artery CTA were randomly assigned into four groups according to the injection protocol.Cases in group 1 to group 3 adopted the injection rate of 4,5 and 6 ml/s respectively,and used automatic threshold preset at 300 HU to trigger the initiation of the scan,with total contrast dose of 1.5 ml/kg body weight.Cases in the group 4 adopted an injection rate of 6 ml/s,triggering threshold of 120 HU,and 1.0 ml/kg body weight of contrast.High density contrast(350 mgI/ml)was used in all cases.The CT values of pulmonary artery,superior vena cava,aortic artery and bronchial artery before and after enhanced scanning were measured in the 4 groups.Numbers of cases with excellent image quality of bronchial artery display were also evaluated.Results:The CT values of pulmonary artery and superior vena cava among four groups hadn’t significant difference(P > 0.05).The CT values of aortic artery in group 4 were higher than other three groups significantly(P < 0.05).The CT values of bronchial artery in group 4 were higher than group 1 and group 2 significantly(P < 0.05).The excellent rate of bronchial artery CTA for group one to group four were: 50%,55%,65% and 80%,respectively.Conclusion:This research showed that the injection rate of 6 ml/s,triggering threshold of 120 HU,1.0 ml/kg body weight of high density contrast dose provide higher contrast,and it’s on optimal protocol for bronchial artery CTA.更多还原