颈动脉颅外段血管成像的最佳速率选择

目的：通过比较使用不同注射速率所获得的多层螺旋CT颈动脉造影(CTC)重建图像，优化注射速率的选择。方法：85例患者随机分为2组，各为30例和55例，注射速率分别为2．0ml／s或3．5ml／s，首先于第六颈椎水平行同层面动态扫描，对比剂剂量为0．3ml／kg，利用小剂量试验软件绘制出时问一密度曲线，确定最佳延迟扫描时问。然后，对每个病例分别以与同层动态扫描时相同的速率进行多层螺旋CT颈动脉造影，并对其CTC重建图像评分。结果：速率3．5mL／s与速率2．0ml／s所得CTA图像综合评分差异具有显著性意义。3．5ml／s所得图像明显优于2．0ml／s所得图像。结论：快速法(3．5ml／s)多层螺旋CT颈动脉造影的成像质量优于慢速法(2．0ml／s)。

Optimal injection rate choice in multi-slice CT angiography on extracranial carotid

Objective:To choose optimal injection rate in multi slice spiral CT carotid angiography by comparing CTA images through using different injection rates.Methods:Eight five patients were randomly divided into two groups (30 and 55 cases in each group), injection rate were 2.0ml/s (slow group) and 3.5ml/s(rapid group), firstly single level dynamic scan was completed at C 6 level with the initial contrast dose(0.3ml/kg),then the optimal delay time was found through the time density curves,CTA were perfomed for each patient with the same delay time and injection rate described above, both MPVR(multi projection volume reconstruction) and MIP(maximum intensity projection)were employed for reconstruction,all images were ranked according to the grade of carotid by 2 radiologists.Results:The difference in imaging grades between the 2.0ml/s (slow group) and3.5ml/s (rapid group) is significant ,rapid group was better than slow one at the average score of imaging.Conclusion:The quality of 3D CTC image of rapid injection rate (3.0)ml/s is superior to that of slow injecion rate (1.5ml/s).