非对比剂磁共振血管成像评估胡桃夹综合征的可行性研究

The Feasibility Study of Diagnosing Nutcracker Syndrome by Non-Contrast Medium Magnetic Resonance Angiography

目的探讨非对比剂磁共振血管成像(NC-MRA)评估肠系膜上动脉(SMA)、腹主动脉(AA)和肾静脉(RV)的解剖关系及左肾静脉(LRV)受压情况的可行性研究。资料与方法搜集MSCTA或CE-MRA诊断为胡桃夹综合征的9例患者,在1.5TMRI上采用多翻转恢复空间标记脉冲(SLEEK)标记动脉血、静脉血分别显示动脉系统(SMA与AA)和静脉系统(RV),最后移除所有翻转带扫描同时显示SMA、AA和RV。由两名放射科主任医师评估NC-MRA的图像质量及SMA、AA和RV解剖关系;LRV受压情况。测量SMA与AA之间的夹角(a),在LRV横断面上分别测量SMA和AA间隙内LRV的最小面积(S1)及近左肾侧LRV的最大面积(S2),并计算S2和S1的比值(q),与MSCTA及CE-MRA对照,并进行统计学分析。结果 NC-MRA在显示SMA、AA和RV的解剖关系及LRV受压情况与MSCTA和CE-MRA具有很好的相关性。NC-MRA测量SMA与AA的夹角(a)平均值,S2和S1及S2与S1比值(q)的平均值分别为22.19、(0.23±0.10)cm2、(0.89±0.29)cm2、4.30;而MSCTA和CE-MRA测得的平均值分别为22.11、(0.24±0.09)cm2、(0.82±0.23)cm2、3.97;它们之间均无统计学意义(P>0.05)。NC-MRA分别显示动脉系统(SMA与AA)和静脉系统(RV),能有效避免动脉、静脉系统相互干扰;又能同时显示SMA、AA和RV,利于观察它们之间的空间解剖关系。NC-MRA有轻度夸大LRV受压程度的可能性。结论用NC-MRA(SLEEK序列)评估胡桃夹综合征是可行,它是一种经济、无创、对肾功能无损伤的新的检查方法,具有很好的临床价值。

Objective To evaluate the ability of NC-MRA in displaying the anatomical relationship and the adjacent structure between SMA,AA and RV and in showing the degree of LRV compression.Materials and Methods 9 Nutcracker Syndrome（NCS） subjects diagnosed by MSCTA or CE-MRA were collected.A SLEEK prepared 3D FIESTA sequence was developed to present the arterial system（SMA and AA） and venous system（RV） respectively on 1.5 T MRI systems,and to display them simultaneously when removed all inversion.Two experienced radiologists evaluated the image quality of NC-MRA and estimated the degree of LRV compression,observed the angle（a）between SMA and AA,measured the cross areas of LRV through the angle（S1）and at the largest diameter of near the renal hilum（S2）,and calculated the ratio（q） of S2 to S1.Results The excellent correlation between NC-MRV and MSCTA（CE-MRA） was found in predicting the presence of anatomical relationship and the adjacent structure between SMA,AA and RV and in showing the degree of LRV compression.The value of a,S1,S2 and q with NC-MRA was 22.190,（0.23±0.10） cm2,（0.89±0.29） cm2,4.30,and the value of a,S1,S2 and q with MSCTA（CE-MRA）was 22.110,（0.24±0.09） cm2,（0.82±0.23） cm2,3.97.There were not significant differences between NC-MRV and MSCTA（CE-MRA）.The respective presentation of the arterial system and venous system（RV） on NC-MRA made for avoiding the interferences between arterial and venous system.The simultaneous presentation of the arterial system and venous system（RV） was in favor of observing the anatomical relationship between them.In addition,NC-MRA had the possibility of overestimating lightly the degree of LRV compression.Conclusion NC-MRA with a SLEEK sequence is feasible for evaluating Nutcracker Syndrome,which is a economical,noninvasive examination.