Biomedical Simulations and Imaging Lab., School of Electrical and Computer Engineering, National Technical University of Athens, Athens, Greece.
Medical School, National and Kapodistrian University of Athens, Athens, Greece.
Sci Rep. 2020 Jul 8;10(1):11221. doi: 10.1038/s41598-020-65340-2.
Asynchronous movement of the carotid atheromatous plaque from B-mode ultrasound has been previously reported, and associated with higher risk of stroke, but not quantitatively estimated. Based on the hypothesis that asynchronous plaque motion is associated with vulnerable plaque, in this study, synchronisation patterns of different tissue areas were estimated using cross-correlations of displacement waveforms. In 135 plaques (77 subjects), plaque radial deformation was synchronised by approximately 50% with the arterial diameter, and the mean phase shift was 0.4 s. Within the plaque, the mean phase shifts between the displacements of the top and bottom surfaces were 0.2 s and 0.3 s, in the radial and longitudinal directions, respectively, and the synchronisation about 80% in both directions. Classification of phase-shift-based features using Random Forests yielded Area-Under-the-Curve scores of 0.81, 0.79, 0.89 and 0.90 for echogenicity, symptomaticity, stenosis degree and plaque risk, respectively. Statistical analysis showed that echolucent, high-stenosis and high-risk plaques exhibited higher phase shifts between the radial displacements of their top and bottom surfaces. These findings are useful in the study of plaque kinematics.
颈动脉粥样硬化斑块的超声 B 型模式下的异步运动先前已有报道，与更高的中风风险相关，但尚未进行定量评估。基于异步斑块运动与易损斑块相关的假设，本研究使用位移波形的互相关来估计不同组织区域的同步模式。在 135 个斑块（77 个患者）中，斑块的径向变形与动脉直径大致同步，平均相位差为 0.4s。在斑块内，上下表面位移之间的平均相位差分别为 0.2s 和 0.3s，在径向和纵向方向上的同步度约为 80%。使用随机森林对基于相位差的特征进行分类，在回声、症状、狭窄程度和斑块风险方面的曲线下面积评分分别为 0.81、0.79、0.89 和 0.90。统计分析表明，回声不均匀、高狭窄和高风险斑块的上下表面的径向位移之间的相位差更高。这些发现对斑块运动学的研究很有用。
