NCE-MRA评估动脉粥样硬化型肾动脉狭窄的应用价值

Application Value of NCE-MRA in Evaluating Atherosclerotic Renal Artery Stenosis

目的以血管内超声成像(IVUS)为标准,对比CT血管造影(CTA)研究结合时间-空间双重标记反转恢复序列(Time-SLIP)的非对比增强MR血管成像(NCE-MRA)在评估动脉粥样硬化型肾动脉狭窄(ARAS)的应用价值。方法搜集29例临床确诊为ARAS并同期进行了CTA和IVUS检查的患者,运用结合Time-SLIP技术采用真实稳态自由进动序列(true SSFP)对狭窄侧肾动脉进行NCE-MRA检查,评估图像质量和血管狭窄程度,分析血管最狭窄处斑块形态特征,并与CTA和IVUS结果进行比较。结果29例患者共有43支肾动脉纳入研究,NCE-MRA图像优秀31支,良好8支,一般4支。以IVUS为标准,CTA和NCE-MRA对ARAS狭窄程度评估结果有明显相关性(r=0.927,P<0.01)。以IVUS为标准,CTA和NCE-MRA总体评价AS斑块的敏感度和特异度分别为92.5%和93.3%、89.2%和91.7%(P均<0.05),其中CTA和NCE-MRA在鉴别斑块纤维组织成分具有极好的一致性(k分别=0.818和0.857,P<0.05),NCE-MRA在鉴别脂质核心和近期破裂出血与IVUS具有高度一致性(k分别=0.695和0.711,P<0.05),但CTA在鉴别斑块钙化与IVUS具有极好的一致性(k=1)。结论结合Time-SLIP的肾动脉NCE-MRA可有效应用于评估导致肾动脉狭窄的AS斑块的主要构成成分并评估其稳定性,能够为临床选择治疗措施提供比CTA更有价值的参考信息。

Objective To assess the application value of Time-SLIP non-contrast enhanced MR angiography(NCE-MRA)in evaluating atherosclerotic renal artery stenosis(ARAS),while regarding intravascular ultrasound(IVUS)as a standard and comparing with CT angiography(CTA).Methods 29 patients with clinically diagnosed ARAS who underwent CTA and IVUS were concurrently treated with Time-SLIP using true steady-state free-precession(true SSFP)versus stenosis.The renal artery was examined by NCE-MRA,and the image quality and degree of vascular stenoses were evaluated.The morphological characteristics of the plaque at the narrowest point of the vessel were analyzed and compared with the results of CTA and IVUS.Results A total of 43 renal arteries were included in 29 patients.The NCE-MRA images were excellent in 31 cases(72%),good in 8 cases(19%),and generally in 4 cases(9%).Based on IVUS,CTA and NCE-MRA were significantly correlated with the assessment of ARAS stenosis(r=0.927,P<0.01).Based on IVUS,CTA and NCE-MRA evaluated the sensitivity and specificity of AS plaques to 92.5%and 93.3%,89.2%and 91.7%,respectively(P<0.05),in which CTA and NCE-MRA were used to identify plaques.The fibrous tissue components had excellent concordance(k=0.818 and 0.857,respectively,P<0.05).NCE-MRA was highly consistent with IVUS in identifying lipid core and recent rupture(k=0.695 and 0.711,respectively P<0.05),but CTA has excellent agreement(k=1)in identifying plaque calcification and IVUS.Conclusion The renal artery NCE-MRA imaging technique combined with Time-SLIP can be effectively applied to evaluate the main components of AS plaques leading to renal artery stenosis and evaluate its stability,which can provide a more valuable reference for clinical selection of treatment measures than CTA.