肝肿瘤消融术增强可视化微波消融针头结构设计与力学性能研究

The Structural Design and Mechanical Performance of Microwave Ablation Needle for Enhanced Visualization in Hepatic Tumor Ablation

摘要: 肝癌高发病率下，微波消融针头的力学性能直接影响治疗精度与安全性。本研究采用有限元仿真对比六棱多面、环形凹槽、表面凹点和六切割面四种针头设计，重点分析支反力–位移曲线及应力云图。结果表明：六棱多面针头穿刺力最高且过程平稳，但尖端应力集中显著增加组织损伤风险；环形凹槽针头通过表面优化使尖端应力降低21%；表面凹点设计穿刺力最低(较基准降低34%)，兼具操作稳定性，适用于低力穿刺场景；六切割面针头在保持低穿刺力(<2.5 N)的同时展现最优位移控制能力。研究证实几何结构与表面特征的协同优化可有效平衡穿刺力学性能与组织损伤控制，其中环形凹槽和六切割面设计综合表现突出，为临床针头选型提供量化依据。后续需结合材料生物相容性与微波传导特性开展多物理场耦合优化，以全面提升微波消融治疗效果。

Abstract: With the high incidence of hepatocellular carcinoma, the mechanical performance of microwave ablation needles critically affects treatment precision and safety. This study employed finite element simulation to compare four needle designs: hexagonal polygonal, annular groove, surface dimpled, and hexagonal cutting-edge configurations. Key parameters including reaction force-displacement curves and stress nephograms were analyzed. Results demonstrated that the hexagonal polygonal needle required the highest insertion force (maintaining process stability) but exhibited significant stress concentration at the tip, increasing tissue injury risks. The annular groove design reduced tip stress by 21% through surface optimization. The surface-dimpled needle achieved the lowest insertion force (34% reduction from baseline) with operational stability, suitable for low-force scenarios. The hexagonal cutting-edge configuration maintained low insertion force (<2.5 N) while demonstrating optimal displacement control. Geometric-structural and surface-feature optimizations effectively balanced mechanical performance with tissue protection, with annular groove and hexagonal cutting-edge designs showing superior comprehensive performance. These findings provide quantitative evidence for clinical needle selection. Future research should integrate material biocompatibility and microwave transmission characteristics through multiphysics coupling optimization to enhance therapeutic outcomes.