Biomedical Technical System Department, Bauman Moscow State Technical University, 105005, 5 Baumanskaya 2-ya str., Moscow, Russia.
Biomedical Technical System Department, Bauman Moscow State Technical University, 105005, 5 Baumanskaya 2-ya str., Moscow, Russia.
Med Eng Phys. 2022 Feb;100:103745. doi: 10.1016/j.medengphy.2021.103745. Epub 2021 Dec 23.
The article describes the research of a new treatment method of lower limb varicose vein using low-frequency ultrasound. To study the effectiveness of this method we analyzed the interaction between the ultrasound instrument and the venous wall and defined the mechanisms of action during endovenous ultrasound treatment (EUT): thermal, mechanical, and chemical. We developed three models to study the impact of different combinations of mechanisms of action on varicose venous wall. The first model describes the endothelial cell layer delamination during mechanical mechanism. Other models investigate the two main modes of EUT. The EUT mode 1 models mechanical and thermal mechanisms of action, while the EUT mode 2 also studies the impregnation process of sclerosant. During the finite element analysis of both EUT modes, the instrument with an axisymmetric tip was inserted inside the vein with varying blood flow velocity. The amplitude of ultrasound oscillations required for the endothelial cell layer delamination was equal to 40 µm. The ultrasound exposure induced the impregnation enhancement of sclerosant up to 6 times. The temperature distribution and the necrotic tissue fraction of the venous wall were also evaluated. The results of the study demonstrate uniform irreversible damage to the venous wall for both EUT modes.
这篇文章描述了一种使用低频超声治疗下肢静脉曲张的新方法的研究。为了研究这种方法的有效性，我们分析了超声仪器与静脉壁的相互作用，并确定了静脉内超声治疗（EUT）过程中的作用机制：热、机械和化学。我们开发了三个模型来研究不同作用机制组合对静脉曲张静脉壁的影响。第一个模型描述了机械机制作用下的内皮细胞层分层。其他模型则研究了 EUT 的两种主要模式。EUT 模式 1 模型研究了机械和热作用机制，而 EUT 模式 2 还研究了硬化剂的浸渍过程。在两种 EUT 模式的有限元分析中，带有轴对称尖端的仪器插入具有不同血流速度的静脉内。内皮细胞层分层所需的超声振动幅度等于 40µm。超声辐射诱导硬化剂浸渍增强高达 6 倍。还评估了温度分布和静脉壁的坏死组织分数。研究结果表明，两种 EUT 模式都能对静脉壁造成均匀的不可逆转损伤。
