超声造影观察颈动脉斑块易损性的研究

Vulnerability of Atherosclerotic Plaque Through Contrast-enhanced Ultrasonography

目的探讨超声造影评估颈动脉粥样硬化斑块易损性的可行性。资料与方法选取经颈动脉超声检查发现动脉粥样硬化斑块的34例患者,均行超声造影检查,观察斑块内有无造影剂增强及增强特征,应用时间-信号强度曲线计算斑块峰值强度(PI)、达峰时间(TTP)、增强密度(DE)。结果软斑组及混合斑组造影剂增强比率分别为100.0%(18/18)、85.7%(12/14),差异无统计学意义(χ2=0.847,P>0.05)。肩部、基底部、尾部增强斑块分别为70.0%、23.3%、6.7%,差异有统计学意义(χ2=29.100,P<0.001),增强斑块在各部位分布比率从高到低依次为肩部>基底部>尾部。增强斑块与部位顺序呈正相关(r=0.404,P<0.01)。软斑组与混合斑组的TTP比较,差异无统计学意义(t=0.479,P>0.05)。软斑组及混合斑组的PI及DE比较,差异有统计学意义(t=7.497、12.224,P<0.05)。结论超声造影能够显示颈部动脉粥样硬化斑块内的新生血管,有助于斑块易损性的评估。

Purpose To investigate the feasibility to diagnose and evaluate the vulnerability of the atherosclerotic plaque through contrast-enhanced ultrasonography. Materials and Methods Thirty-four patients with carotid atherosclerosis were enrolled in the study to take contrast-enhanced ultrasonography and were observed on whether the plaque was enhanced and the features of its enhancement. The peak intensity （PI）, time to peak （TTP）, and density echo （DE） were calculated according to the time-intensity curve with QLAB software. Results The ratio of enhanced malacoplakia and the mixed plaque showed no difference （χ^2=0.847, P〉0.05）. The percentages of enhanced plaque distributed on the base, tail and the shoulder were 70.0%, 23.3% and 6.7%, respectively with significant difference （χ^2=29.100, P〈0.001）; the distribution ratio of enhanced plaque from high to low were as follows： the plaque on the shoulder 〉 the plaque on the base＆gt; the plaque on the tail. It was positively correlated between enhanced plaque and its distribution （r=0.404, P〈0.01）. The TTP of the ROI between the malacoplakias and the mixed plaques showed no difference （t=0.479, P〉0.05）. The PI and DE of the ROI in the malacoplakia and the mixed plaques were analyzed by the time-intensity curve and the differences proved to be statistically significant （t=7.497 and 12.224, P〈0.05）. Conclusion Contrast-enhanced ultrasonography could present the neovessels in the atherosclerotic plaque, which is helpful in evaluating the vulnerability of atherosclerotic plaque.