血管内膜中膜自动跟踪技术评价颈动脉孤立性斑块生物力学特性  

Biomechanical characteristics of carotid isolated plaques using intima-media thickness automatic tracking technique

作　　者：李妙[1] 张平洋[1] 马小五[1] 董静[1] 吴文芳[1] 丁钱山 

机构地区：[1]南京医科大学附属南京医院南京市第一医院心血管超声科

出　　处：《中国动脉硬化杂志》2018年第2期171-175,共5页Chinese Journal of Arteriosclerosis

基　　金：南京市2015年度科技发展计划(医疗卫生与国际合作)项目(201503022)

摘　　要：目的 应用血管内膜中膜自动跟踪技术结合声学密度定量评价颈动脉孤立性斑块的生物力学特性。方法 随机选取体检发现有颈动脉孤立性斑块的患者30例,运用血管内膜中膜自动跟踪技术观测斑块以及斑块上游、顶部及下游区域的内膜中膜厚度变化特点,计算每个区域内膜中膜应变率（SR）、时间应变率（TR）,得出不同区域斑块的参数。与此同时,应用声学密度定量（AD）技术测量斑块上述相应区域的校正声学密度值（corrected average image intensity value,AIIc%）,以同侧颈动脉邻近斑块的正常内膜作为对照组,将所有参数进行比较。此后,根据斑块厚度（IMT）将斑块分成三组：小斑块组（1.2 mm2.5 mm）,分析比较不同厚度斑块组SR、TR及AD,并探讨SR、TR与斑块厚度之间的关系。结果 斑块组SR、TR均较正常内膜（对照组）降低（P〈0.05）。斑块上游的SR值高于顶部（P〈0.05）,TR值高于斑块下游（P〈0.05）;斑块顶部SR、TR值均高于斑块下游（P〈0.05）。斑块顶部及斑块下游SR、TR均较对照组降低（P〈0.05）。校正密度值AIIc%在斑块上游及顶部比下游低（P〈0.05）,而上游与顶部之间未见明显统计学差异。斑块上游、顶部及下游部位的AIIc%均高于对照组（P〈0.05）。校正密度值AIIc%与SR、TR呈负相关（r=-0.63,r=-0.58,P〈0.05）。三个不同厚度斑块组TR、SR差异无统计学意义。结论 血管内膜中膜自动跟踪技术结合声学密度定量可以较准确测定颈动脉孤立性斑块应变及组织密度的不均衡性,有望成为早期评价颈动脉斑块生物力学特性的无创、简捷的新方法。Aim To assess the biomechanical characteristics of carotid isolated plaques using intima-media thickness （IMT） automatic tracking technique. Methods The study included 30 patients who had isolated plaques in carotid artery. IMT strain rate （SR）, IMT time strain rate （TR） and AIIc% were measured by IMT automatic tracking technique along with acoustic densitometry （AD） to assess the variation of the IMT and acoustic density in the upstream, fibrous cap top and downstream regions of the plaque and ipsilateral normal carotid. All plaques were divided into three groups according to IMT： small group （ 1.2 mm〈IMT〈l.5 ram）, moderate group （ 1.5 mm〈IMT〈2.5 mm） and large group （IMT〉2.5 mm）. The differences of SR, TR and AIIc% were identified among three groups. Results SR and TR were significantly reduced in plaques group compared with controls. Compared with cap top area （ CTA）, the SR of up- stream area （UA） were significantly increased. However, the SR, TR of downstream area （DA） were significantly lower than CTA and UA. Compared with control, the SR, TR were significantly reduced in CTA and DA. AIIc% in UA and CTA were significantly lower than DA. AIIc% in all three regions were significantly higher than that in control group. The SR, TR for the 3 plaque regions were negatively correlated with AIIc% （r=-0.63, r=-0.58, P〈0.05）. The SR, TR among three groups showed no statistical significance. Conclusion IMT automatic tracking along with AD could be applied to identify the anisotropic biomechanical features in carotid isolated plaques, which may be a new noninvasive way to early assess the biomechanical properties of carotid plaque.

关 键 词：血管内膜中膜自动跟踪技术 颈动脉孤立性斑块 力学特性 声学密度定量技术 

分 类 号：R445.1[医药卫生—影像医学与核医学]