Department of General Surgery, Huashan Hospital, Fudan University, Shanghai, China.
State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China.
Ultrason Sonochem. 2023 Oct;99:106562. doi: 10.1016/j.ultsonch.2023.106562. Epub 2023 Aug 20.
Ultrasound-induced cavitation in blood vessels is a common scenario in medical procedures. This paper focuses on understanding the mechanism of microscopic damage to vessel walls caused by the evolution of cavitation bubbles within the vessels. In this study, cavitation bubbles were generated using the low-voltage discharge method in 0.9% sodium chloride saline, and vessel models with wall thicknesses ranging from 0.7 mm to 2 mm were made using a 3D laminating process. The interaction between cavitation bubbles and vessel models with different wall thicknesses was observed using a combination of high-speed photography. Results show that cavitation bubble morphology and collapse time increased and then stabilized as the vessel wall thickness increased. When the cavitation bubble was located in vessel axial line, pair of opposing micro-jets were formed along the axis of the vessel, and the peak of micro-jet velocity decreased with increasing wall thickness. However, when the cavitation bubble deviated from the vessel model center, no micro-jet towards the vessel model wall was observed. Further analysis of the vessel wall deformation under varying distances from the cavitation bubble to the vessel wall revealed that the magnitude of vessel wall stretch due to the cavitation bubble expansion was greater than that of the contraction. A comparative analysis of the interaction of between the cavitation bubble and different forms of elastic membranes showed that the oscillation period of the cavitation bubble under the influence of elastic vessel model was lower than the elastic membrane. Furthermore, the degree of deformation of elastic vessel models under the expansion of the cavitation bubble was smaller than that of elastic membranes, whereas the degree of deformation of elastic vessel models in the contraction phase of the cavitation bubble was larger than that of elastic membranes. These new findings provide important theoretical insights into the microscopic mechanisms of blood vessel potential damage caused by ultrasound-induced cavitation bubble, as well as cavitation in pipelines in hydrodynamic systems.
血管中的超声空化是医学程序中的常见现象。本文重点研究了在血管内空化泡演变过程中，血管壁微观损伤的机制。在这项研究中，使用低压放电法在 0.9%氯化钠盐水中产生空化泡，并使用 3D 层压工艺制作厚度为 0.7mm 至 2mm 的血管模型。使用高速摄影术组合观察了不同壁厚的空化泡与血管模型之间的相互作用。结果表明，随着血管壁厚的增加，空化泡形态和崩溃时间先增加后稳定。当空化泡位于血管轴线上时，在血管轴线上形成了一对相反的微射流，微射流速度峰值随着壁厚的增加而降低。然而，当空化泡偏离血管模型中心时，没有观察到朝向血管模型壁的微射流。进一步分析空化泡与血管壁之间不同距离下的血管壁变形表明，由于空化泡膨胀导致的血管壁拉伸幅度大于收缩幅度。对空化泡与不同形式的弹性膜相互作用的比较分析表明，在弹性血管模型的影响下，空化泡的振荡周期低于弹性膜。此外，在空化泡膨胀阶段，弹性血管模型的变形程度小于弹性膜，而在空化泡收缩阶段，弹性血管模型的变形程度大于弹性膜。这些新发现为超声空化泡引起的血管潜在损伤的微观机制以及流体动力学系统中空化泡在管道中的空化提供了重要的理论见解。
