高分辨MR血管壁成像对脑血管支架植入术后的随访评估价值

Value of high-resolution vessel wall imaging in assessing cerebral vascular stents

目的探讨HRVWI对脑血管支架植入术后的随访评估价值。方法收集脑血管支架植入术后病人21例共24根血管,分成单纯支架组(10根)和支架辅助弹簧圈组(14根),术后半年首次采用DSA随访检查,以后每年随访一次,选择2017年~2019年间住院DSA复查的病人并于DSA检查前一周内完成HRVWI、CEMRA检查。随访时间半年~9年不等。采用4分法评估支架段血管结构显示情况,按伪影由重到轻分别为赋予1~4分,以DSA为参考金标准。采用Wilcoxon秩和检验比较HRVWI和CEMRA对支架段血管结构显示的差异。用Bland-Altman图像法和Pearson相关分析检验HRVWI与DSA对支架狭窄率测量的一致性。结果DSA复查发现2支支架重度狭窄,1支中度狭窄,21支轻度狭窄。14个被栓塞的动脉瘤均未复发。单纯支架组:HRVWI和CEMRA评分分别为(2.900±0.737)、(1.800±0.918),差别有统计学意义(Z=-2.598,P=0.009);支架辅助弹簧圈组:两者评分分别为(3.142±0.363)、(1.571±0.0.513),差别有统计学意义(Z=-3.372,P=0.001)。HRVWI测量的支架狭窄率与DSA随访测量的狭窄率高度相关,r=0.995,P<0.05。Bland-Altman图反映绝大多数据点在一致性界限内(x±1.96 s)。结论HRVWI对支架段脑血管结构显示优于CEMRA,对管腔狭窄程度的判断与DSA有高度的一致性,是一种很好的随访手段。

Objective To compare high-resolution vessel wall imaging(HRVWI)and contrast-enhanced MR angiography(CEMRA)for assessing cerebral vascular stents.Methods 21 patients with vascular stents only(10)and stent-assisted coil embolization(14)underwent HRVWI and CEMRA using a 750 W MR scanner(General Electric Company)within one week before digital subtraction angiography(DSA).Severity of susceptibility artifact within the parent artery was scored using a 4-point scale with DSA as reference standard.Consistency of stenosis rates measured by HRVWI and DSA was compared using Bland-Altman plots and Pearson correlation.Results The susceptibility artifact scores of HRVWI were significantly higher than that of CEMRA in both pure stents(Z=-2.598,P=0.009)and stent-assisted coil embolization(Z=-3.372,P=0.001).There was good correlation between HRVWI and DSA for stenosis rates(r=0.995,P<0.05).Bland-Altman plots showed that most of the data points were within the consistency limit(x±1.96 s).Conclusion HRVWI is superior to CEMRA for depiction of cerebral vessels with stents.The consistency of stenosis rates between HRVWI and DSA is high and both sequences are useful for follow up of vascular stents.