颈动脉分叉血流类型改变对MRA信号影响的实验研究

The experimental study of the effect of blood flow type change at the common carotid artery bifurcation(CCAB) on MR angiographic signal

目的 :探讨颈动脉分叉(CCAB)血流类型改变对MRA信号的影响 ,提高对MRA图像的认识。材料与方法 :健康自愿者20名 ,行双侧CCABDuplexUS和2DTOFMRA对照研究 ,观察CCAB血流类型改变对MRA信号的影响。结果 :20例40个CCABDuplexUS均显示颈内动脉窦后外侧有反向血流 ,2DTOFMRA示该部位血流信号较弱 ,且与颈总动脉分叉夹角成正比 ,在MIP重建图像上可形成狭窄的假象。结论 :了解正常成人颈总动脉分叉部血流类型改变对MRA图像的影响 ,有助于正确分析和解释血管病变的MRA图像。

Objective:To explore the effect of blood flow type change at the CCAB on MR angiographic signal,and improve the ability of understanding MRA films.Methods:20 volunteers with 40 CCABs were comparatively studied with color duplex ultrasonography and 2D time of flight MR angiography,the effect of blood flow type change at the CCAB on MR angiographic signal were analysed.Results:All 40 CCABs have some reverse blood flow showed by Duplex US,and have some MR signal loss by MRA at the posteriolateral side of CCAB,which were ratio to degree of CCAB and pseudostenosis of CCAB could be known in normal adults on MIP reconstruction film.Conclusion:knowing blood flow type change effect on MRA manifestations at the CCAB in normal adults can help one correctly analyse and interpret diseased vessel's MRA findings.