Yao Guang, Wu Maozhong, Lai Jianhua, Lv Youcheng, Zheng Lijuan, Wang Chengyong
Guangdong Provincial Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology, Guangdong University of Technology, Guangzhou 510006, China.
Guangdong Provincial Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology, Guangdong University of Technology, Guangzhou 510006, China.
Ultrason Sonochem. 2025 Oct;121:107474. doi: 10.1016/j.ultsonch.2025.107474. Epub 2025 Jul 24.
Effective treatment of diverse vascular occlusions requires precise energy delivery and tissue-specific ablation strategies. This study systematically investigates the coupled mechanical vibration and cavitation mechanisms of a novel flexible ultrasonic guidewire during ablation of calcified, lipid-rich, and thrombotic occlusion mimics. Integrating numerical simulations and experimental validation, this work elucidates the dynamic interplay between ultrasonic parameters and tissue-specific ablation outcomes. For calcified mimics, mechanical vibrational impact is the dominant ablation mechanism, achieving substantial material removal primarily through fracture. Lipid-rich tissue ablation is driven by emulsification via cavitation microjets and acoustic streaming, generating microparticles with sizes of 10-250 μm, controllable by ultrasonic power. Thrombus ablation involves initial penetration followed by erythrocyte lysis, primarily mediated by transient cavitation. Crucially, guidewire bending significantly attenuates tip vibration amplitude, resulting in a reduction of 14.3-30.9 %, with titanium alloy exhibiting superior energy transmission stability under curvature compared to nickel-titanium. These findings highlight distinct, tissue-dependent ablation paradigms: mechanical fragmentation for hard tissues compared to cavitation and streaming induced emulsification or lysis for soft tissues. This mechanistic understanding is foundational for designing adaptive ultrasonic guidewires capable of adjusting energy delivery modes based on real time feedback of tissue characteristics, thereby enhancing the precision and efficacy of endovascular interventions.
有效治疗各种血管闭塞需要精确的能量传递和组织特异性消融策略。本研究系统地研究了一种新型柔性超声导丝在消融钙化、富含脂质和血栓性闭塞模拟物过程中的耦合机械振动和空化机制。通过整合数值模拟和实验验证，这项工作阐明了超声参数与组织特异性消融结果之间的动态相互作用。对于钙化模拟物，机械振动冲击是主要的消融机制，主要通过断裂实现大量物质去除。富含脂质的组织消融由空化微射流和声流引起的乳化驱动，产生尺寸为10 - 250μm的微粒，可通过超声功率控制。血栓消融包括初始穿透，随后是红细胞裂解，主要由瞬态空化介导。至关重要的是，导丝弯曲会显著衰减尖端振动幅度，导致振动幅度降低14.3 - 30.9%，与镍钛合金相比，钛合金在弯曲情况下表现出卓越的能量传输稳定性。这些发现突出了不同的、依赖于组织的消融模式：硬组织采用机械破碎，而软组织采用空化和声流诱导的乳化或裂解。这种机理理解是设计能够根据组织特征的实时反馈调整能量传递模式的自适应超声导丝的基础，从而提高血管内介入治疗的精度和疗效。
