非对比增强SPACE FLOW序列与CT静脉造影在髂静脉压迫综合征诊断中的对照研究

The Comparative Study of Non-Contrast Enhanced SPACE FLOW Sequence and CT Venography in the Diagnosis of Iliac Vein Compression Syndrome

目的探讨非对比增强磁共振血管成像SPACE FLOW技术在髂静脉压迫综合征的临床应用价值。方法搜集临床上明确诊断髂静脉压迫综合征的患者64例,在进行下肢直接法CTV的前后2天内采用西门子Prisma 3.0T进行非对比增强磁共振血管检查,扫描序列包括True-fisp、T_(1) SPACE及SPACE FLOW。运用主观评分对比SPACE FLOW序列及下肢直接法CTV检查的图像质量;分别在两组图像上测量患侧髂总静脉最大受压处最短径、同层面对侧髂总静脉最短径、患侧髂总静脉远端最短径及对侧髂总静脉远端最短径,并根据1-(患侧髂总静脉最大受压处最短径/对侧髂总静脉远端最短径)计算出狭窄率,对比两组检查所得直径及狭窄率的差异;评价盆腔内侧支循环显示差异。结果两名医师对SPACE FLOW图像与下肢直接法CTV图像进行图像质量主观评分一致性良好,Kappa值分别为0.75和0.69,两种成像方式横轴位图像质量评分差异无统计学意义。SPACE FLOW在患侧髂总静脉最大受压处最短径值、同层面对侧髂总静脉最短径值、患侧髂总静脉远端最短径值及对侧髂总静脉远端最短径值均较CTV所测值低,差异均有统计学意义(P<0.05)。同时,两种方法测得的狭窄率不同,SPACE FLOW测得狭窄率(54.92±23.54)%较CTV测得狭窄率(51.45±21.94)%大,二者差异有统计学意义(P=0.017);运用Bland Altman图可见两组测量狭窄率一致性较好。SPACE FLOW盆腔侧支血管显示率与CTV相比有统计学差异(P<0.001);两种方法显示侧支循环一致性良好,Kappa值为0.620。结论SPACE FLOW序列对比下肢CTV在评价髂静脉狭窄程度的一致性高,显示侧支循环的一致性良好,可作为临床诊断髂静脉压迫综合征的另一种辅助检查方法。

Objective To explore the clinical value of non-contrast enhanced magnetic resonance angiography SPACE FLOW technique in iliac vein compression syndrome.Methods A total of 64 patients with iliac vein compression syndrome diagnosed clinically in our hospital were collected.Non-contrast enhanced magnetic resonance angiography imaging was got at Siemens Prisma 3.0 T within 2 days before or after the direct lower extremity CTV exam.The scanning sequence included True-fisp,T_(1) SPACE and SPACE FLOW.The image quality of SPACE FLOW and CTV was subjectively scored;the shortest diameter of the maximum compression of the common iliac vein,the shortest diameter of the contralateral common iliac vein,the shortest diameter of the distal common iliac vein and the shortest diameter of the contralateral distal common iliac vein were measured on the two sets of images respectively.The stenosis rate was calculated according to(the shortest diameter of the maximum compression of the common iliac vein/the shortest diameter of the contralateral distal common iliac vein),and the differences in the diameter and stenosis rate obtained by examination were compared between the two groups.The differences of the collateral vessels in the pelvis were evaluated.Results The subjective scores of image quality between SPACE FLOW images and CTV images by two physicians were consistent,with Kappa values of 0.75 and 0.69 respectively.There was no significant difference in horizontal image quality scores between the two methods.the shortest diameter of the maximum compression of the common iliac vein,the shortest diameter of the contralateral common iliac vein,the shortest diameter of the distal common iliac vein and the shortest diameter of the contralateral distal common iliac vein measured by SPACE FLOW were significantly different from those in group CTV.The diameter of 4 points in SPACE FLOW group were lower than that in CTV group.The differences were statistically significant.The stenosis rates measured by the two methods were statistically different.P=0.017;The stenosis rate measured by SPACE FLOW was higher than that measured by CTV,(54.92±23.54)%vs(51.45±21.94)%.It can be seen that the two groups have good consistency in the measurement of stenosis rate using the Bland Altman diagram.Compared with CTV,the display rate of pelvic collateral vessels in SPACE FLOW was statistically different,P<0.001.The two methods showed good consistency of collateral circulation,and the Kappa value was 0.620.Conclusion The SPACE FLOW sequence has high consistency in evaluating the degree of iliac vein stenosis compared with lower extremity CTV,and it shows good consistency of collateral circulation.It can be used as another auxiliary examination method for clinical diagnosis of iliac vein compression syndrome.