VE-ASL MRI评价脑动脉侧支循环——与DSA比较  

Visualizing cerebral arterial collaterals:MRI using vessel-encoded arterial spin labeling perfusion imaging compared with DSA

作　　者：吴冰[1] 王霄英[2] 郭佳[2] 莫大鹏[3] Eric C.Wong 张珏[2] 黄一宁[5] 

机构地区：[1]北京军区总医院放射诊断科,北京100700 [2]北京大学前沿交叉学科研究院功能成像研究中心,北京100871 [3]北京大学第一医院神经外科,北京100034 [4]Center for Functional Magnetic Resonance Imaging and Department of Radiology,University of California [5]北京大学第一医院神经内科,北京100034

出　　处：《放射学实践》2012年第7期722-725,共4页Radiologic Practice

摘　　要：目的:使用血管编码动脉自旋标记(VE-ASL)技术在评价颈动脉狭窄患者通过Willis环与软脑膜动脉形成的侧支循环中的价值。方法:对经超声检查诊断为单侧颈内动脉中度以上狭窄或大脑中动脉血流速度明显增加的10例患者,行VE-ASL MRI检查,测量连续7个脑部层面(层厚8mm,间隔2mm),使用红绿蓝三种伪彩色分别标记来源于右侧颈内动脉、左侧颈内动脉和后循环的血流。所有患者在MRI检查前后1周内行DSA检查。将狭窄侧大脑半球侧支循环情况分为4种类型。Ⅰ型:仅来源于对侧颈内动脉;Ⅱ型:仅来源于后循环;Ⅲ型:既来源于对侧颈内动脉,也来源于后循环;Ⅳ型:既无对侧颈内动脉供血,也无后循环的侧支供血。记录患者侧支血流中软脑膜动脉侧支的数目。计算卡帕值比较两种测量方法之间的一致性。结果:比较VE-ASL和DSA方法,DSA对侧支循环的分型结果为Ⅰ型1例,Ⅱ型2例,Ⅲ型5例,Ⅳ型2例;VE-ASL分型结果为Ⅰ型1例,Ⅱ型3例,Ⅲ型4例,Ⅳ型2例。两种检查方法的诊断一致性非常好(Kappa=0.8551,Z=4.421,P<0.0001)10例中观察到6例8处软脑膜侧支血流。结论:对颈内动脉狭窄患者,VE-ASL可以无创地评价脑动脉通过Willis环及软脑膜动脉形成的侧支循环。Objective：To evaluate the collateral flows via the circle of Willis （COW） and leptomeningeal anastomoses using vessel encoded arterial spin labeling （VE-ASL） perfusion imaging. Methods： Ten patients （9 symptomatic, 1 asympto- matic） had unilateral ICA stenosis over 70% or MCA stenosis diagnosed by ultrasonography were investigated by MRI VE- ASL. Seven continuous slices with slice thickness as 8mm and interval as 2ram were measured. Three-colored maps of the left carotid artery,right carotid artery and posterior circulation territories were performed. All patients had DSA 1 week be- fore MRI. The pattern of eollarterals on the side of the stenosis was investigated with VE-ASL and DSA. In each patient the pattern of collateral flow via the circle of Willis or leptomeningeal anastomoses was categorized into 4 types：Type I ,colla- teral flow coming from contralateral ICA only; Type II , from posterior circulation only; Type III, from both contralateral ICA and posterior circulation; Type IV, no collateral flow from either contralateral ICA or the posterior circulation. The number of collateral flow via leptomeninngeal anastomoses was recorded. The results were compared in cross table, and kap- pa coefficient was calculated to determine the agreement between VE-ASL and DSA. Results： Based on DSA findings, there were Type I , （1 patient） ;Type II , （2 patients） ;Type II, （5 patients） ; and Type IV, （2 patients）. Based on VE-ASL fin- dings,there were Type I （1 patient）,Type III（3 patients） , Type III （4 patients） and Type IV （2 patients）. The Kappa value between VE-ASL and DSA was 0. 855, which were agreeable statistically （Z ： 4. 421, P~ 0. 0001）. The collateral flows via leptomeninngeal anastomoses were found in 6 patients （8 brain areas）. Conclusion：VE-ASL could show the collat- eral flow via COW and leptomeningeal anastomoses non-invasively.

关 键 词：颈动脉狭窄 侧支循环 动脉自旋标记 磁共振成像 

分 类 号：R445.2[医药卫生—影像医学与核医学] R814.43[医药卫生—诊断学]