血管回声跟踪技术对兔颈动脉弹性的定量评价研究

Quantitative analysis with echo-tracking technology equipped with probe maintenance tool on carotid elasticity in rabbits

目的探讨探头支架辅助的回声跟踪（echo-tracking，ET）技术定量评价早期动脉硬化的可行性、准确性及各弹性参数的敏感性。方法对39只4月龄健康新西兰白兔随机分为4组，造模1、2、3组及对照组。造模组均饲喂高脂颗粒饲料，对照组饲喂基础颗粒饲料，分别在喂养的0、4、8、12周末，利用探头支架辅助的ET技术测量颈动脉弹性的各项指标：压力应变弹性系数（Ep）、僵硬度（p）及顺应性（AC）、脉搏波速度（PWV）、膨大指数（AI）等，同时取兔耳缘静脉血进行血脂检查及颈总动脉病理检查，进行对照分析。结果Ep、β随造模时间的延长逐渐增加，AC随造模时间的延长逐渐减小，造模4周末与基础状态相比、造模8周末与造模4周末相比、造模12周末与造模8周末相比均出现显著变化，差异均有统计学意义（P〈0．05）；PWV于造模8周末开始较基础状态增高（P〈0．1）5），于造模12周末显著增高且较造模8周末亦显著增高，差异有统计学意义（P〈0．01）；AI始终无明显变化。结论ET技术可准确、可靠地评价早期动脉硬化的动脉弹性，而应用探头支架可保持检查过程的稳定性和结果的敏感性、精确性及可重复性。

Objective To investigate the feasibility, accuracy and sensitivety of echo tracking （ET） technology on carotid elasticity in rabbits. Methods Thirty-nine healthy New Zealand rabbits were divided into 4 groups, which group 1,2,3 were experimental groups and group 4 was control group. Experimental groups were fed with high cholesterol diet, control group were fed with basic diet. The parameters of elasticity of carotid were measured with ET technology, including pressure strain elasticity modulus （ Ep）, stiffness parameter （]3）, arterial cornpliance（AC）,pulse wave velocity（ PWV）,augmentation index（ AI） at the interval of 0,4,8,12 weeks of the experiment respectively. Blood-fat level of all rabbits were checked and the common carotid artery was examined pathologically,which were compared and analyzed then. Results With the prolong of the experiment time,the Ep and β raised,but the AC reduced. There were significant difference between experimental group 1 （4 weeks） and basement,which were same between experimental group 2 （8 weeks） and experimental group 1, between experimental group 3（ 12 weeks） and experimental group 2（ P 〈0.05）. PWV increased comparing with basement in the end of 8 weeks,which increased obviously in the end of 12 weeks,meanwhile was higher than in the end of 8 weeks,which there were significant differences（ P 〈 0. 01）. AI had no change all the time. Conclusions ET technology is accurate and reliable in detecting early atherosclerosis. Probe maintenance tool can keep the steady of checking progress, sensitive of result and repeatability.