颈动脉粥样斑块应变及应变率分布的初步探讨

目的 探讨超声检测颈动脉粥样硬化斑块应变及应变率的可行性，颈动脉粥样硬化斑块应变及应变率的分布情况。方法 选取26例冠心病患者的35处颈动脉斑块，运用组织速度成像(TVI)和Q-analysis软件测量斑块不同部位的位移、斑块应变及应变率的峰值，对同一处斑块分别在不同参数条件下测量斑块应变及应变率峰值。结果 斑块应变和应变率测量值在不同参数条件下差异无显著性意义；不同部位的斑块应变、应变率差异具有显著性意义；急性心肌梗死、陈旧性心肌梗死和心绞痛3组患者颈动脉斑块的受力情况存在差异。斑块肩部和纤维帽表面是应变最集中的部位，并且沿径向方向，从斑块表面至基底部，应变及应变率呈减小趋势。结论 TVI技术可以用于颈动脉斑块应变及应变率的分析。不同类型的斑块肩部及不同部位应变及应变率存在差异。

Preliminary analysis of strain and strain rate distribution in carotid artery atherosclerotic plaque

Objective To explore the feasibility of ultrasonic examination in the strain(S) and strain rate(SR) of carotid artery atheromatous plaque, and the distribution of S and SR of the atherosclerotic plaques. Methods Tissue velocity imaging(TVI) was used in 26 cases of coronary artery disease(CAD),and 35 atherosclerotic plaques in the carotid artery were found.The peak values of displacement, S and SR in different plaque sites were obtained with Q-analysis software. The estimation of S and SR of same sites was acquired in different parametric settings, including S length, S reject and S scale. Results Different parametric settings had no influence upon the estimation of S and SR. However, significant difference of S and SR could be found in different plaque sites, such as the shoulder, the surface of fibrous cap and the base and it was the same case among different acoustic plaque types. S and SR distribution patterns were similar between angina pectoris group and old myocardial infarction group; yet they were significantly different between acute myocardial infarction group and the former two groups. Conclusions TVI technique and ultrasonic Doppler-based strain imaging method could be used in carotid arteries. Strain concentrated mainly on the surface of fibrous cap and the plaque shoulder. SR of plaque shoulder among three acoustic plaque types was different. From the surface to the base axially, S and SR decreased gradually.