主动脉MSCTA对比剂注射方案优化的探讨

Study on the optimizing injection approaches of contrast material in MSCT Aortic angiography

目的比较相同碘浓度和注射速率、不同对比剂注射方案对主动脉多层螺旋CT血管成像(MSCTA)应用效果的影响。方法100例可疑主动脉病变患者随机分为A、B两组(n=50),分别采用不同对比剂注射方案进行主动脉CTA检查:A组注射对比剂100ml,对比剂浓度300mgI/ml,注射速率3ml/s;B组注射对比剂60ml后用40ml生理盐水冲刷,对比剂浓度及注射速率同A组。扫描延迟时间采用自动触发技术。测量升主动脉、胸7(T7)及腰2(L2)水平降主动脉、主动脉分叉处CT值;由两位影像诊断高级职称医师对血管强化程度、重组血管清晰度进行评价。结果两种注射方案在升主动脉、T7及L2水平降主动脉、主动脉分叉处的平均强化程度分别为255HU和240HU,两组间差异不具有统计学意义;两组重组血管清晰度无统计学差异。两侧肾动脉及分支血管清楚显示率为93%。结论应用对比剂60ml注射+40ml生理盐水冲洗行主动脉MSCTA能满足主动脉检查要求,并减少对比剂用量。

Objective To study the effects of different dose of contrast material with the same concentration and the same injection rate on MSCT angiography. Methods One hundred patients suspected aortic-diseases were divided into two groups randomly and underwent MSCT aortic-angiography with two different injection protocols respectively, i.e. group A.. 300 mg/ml×3 ml/s, 100 ml contrast material, group B： 300 mg/ml×3 ml/s, 60 ml of contrast material was injected followed by flushing with 40 ml saline solution. The scanning delay time was adopted by the auto-trigger technique. Regions of interest were marked and their attenuation values were individually and respectively measured in the ascending aorta （AA）, descending aorta （DA） in thoracic vertebra 7, lumbar 2, aortic artery forfieation. The enhancement of arteries and the definition of the reconstructed vessels were evaluated respectively by two experienced doctors. Results The mean degree of enhancement of in the ascending aorta （AA）, descending aorta （DA） in thoracic yertebra 7, lumbar 2, aortic artery forfication were similar （about 255 HU, 240 HU） in group A and group B respectively. the difference between the two groups was insignificant. The quality of reconstruction images between group A and group B was equal, with 93% of images depicting the two kidney arteries and the branches clearly. Conclusion The contrast material injection protocols with 60 ml contrast material ＋40 ml saline is competent for MSCT aortic-angiography, which can reduce the dose of contrast material.