面向生命体活检取样的超声振动辅助生物组织切削机理及应用

To solve the problem of lower efficency and bad accurancy in traditional biopsy, a new biopsy methodology, ultrasonic vibration assisted biopsy, is proposed. The model for the generation and propagation of single crack in the tissue is established based on the in-depth study of the mechanism for the ultrasonic vibration assisted biopsy. The new integrated theory for the ultrasonic vibration assisted biopsy is proposed, and the relationship among sampling efficiency, cutter parameters, feeding parameters and parameters with respect to ultrasonic vibration is deduced. A new design method for the sampling needle is developed with the study of the isomorphism principle between angle relationship in the 3D Euclidean space and 2D Riemann surface. The bend of the sampling needle and the deformation of tissue in the sampling process are analyzed, and then the compensation measures are determined. The integrated material removal model for the biological tissue under ultrasonic vibration and the sliding model for the biological tissue in the needles are established. The sampling effects for the new ultrasonic vibration assisted biopsy technology with the needles in the new shape under different working conditions are studied in depth. The influences of needle structure parameters and driving parameters on this new technology are mastered. The technological database for sampling, which can be used to conduct application of the new ultrasonic vibration assisted biopsy technology with the needles in the new shape, is established. The establishment of the new tissue biopsy theory and the successful development of the new ultrasonic vibration assisted biopsy technology with the new type needles would be of great significance in the reformation of traditional biopsy methodology and the alleviation of discomfort for patients. The technical and economic benefit and the social benefit are remarkable.

针对活检取样效率低、准确度差的难题，提出了超声振动辅助组织切削取样新方法。通过深入研究超声辅助组织切削机理，建立组织单个裂纹产生和扩展模型；提出新的完整的超声振动辅助生物组织切削加工理论，并推导取样效率与刀具参数、进给参数以及超声振动参数之间的关系；探寻三维欧式空间中的角度关系与二维黎曼平面度量关系之间的同构原理，形成取样针设计新方法；分析取样过程中针的弯曲、组织变形，确定补偿措施；建立超声振动作用下的生物组织材料去除模型以及材料在针管内的滑移模型。深入研究新型针头超声振动辅助组织活检取样技术在不同工况下的取样效果，掌握该取样技术与针头参数、驱动参数之间的关系，建立取样工艺数据库，作为指导新型针头超声振动辅助组织活检取样技术应用的基础。新型组织切削理论的建立和新型针头超声振动辅助组织活检取样技术的研制成功对革新传统组织活检取样技术、减轻病人痛苦具有非常重大的意义，技术经济和社会效益显著。

通过机械学科和医学学科相互交叉，解决活检取样过程中取样效率低、准确度差的难题。从单元刀具切削生物组织材料入手，建立了完整的超声振动辅助生物组织切削理论。基于振动辅助切削软组织理论分析，深入研究振动辅助穿刺过程中针与软组织间相互作用机理，对针与组织之间运动学和力学进行分析并建立相关模型。基于断裂力学和能量法，结合冲击载荷和振动对裂纹的影响，分析了裂纹形成与扩展机制，归纳了典型生物软组织的切削断裂机理。基于LuGre动态膜材模型，建立了超声振动动态摩擦模型，分析了超声振动对摩擦特性的影响规律。基于基础力学理论，分析了生物组织加持过程中生/机接触机制，建立了单齿及多齿接触力学分析模型。将穿刺针类比为针端固定的悬臂梁，基于欧拉-伯努利梁理论和叠加理论，运用准静态平衡思想，在2D平面上构建悬臂梁力学模型，推导出了挠曲量计算公式，研究了取样针的挠曲变形特性。开发了一种用于新型针头设计、制造的技术方法。完成了基于非欧几何原理的穿刺活检针针尖主要切削角度的计算模型推导，为复杂空间曲面型穿刺活检针结构的引入建立了理论基础。提出了基于鸟喙结构的新型仿生穿刺活检针结构（喙针）模型，搭建了新型穿刺活检针磨削加工平台，得到了质量可靠的试验用活检针，进行了新型穿刺活检针穿刺取样性能研究试验，开发了活检针针头优化设计软件系统。形成了一种新型的超声振动辅助组织活检取样技术，搭建了的振动辅助穿刺取样装置和超声振动取样装置，系统研究了取样参数对取样效果的影响规律。基于正交试验，优化了取样参数，得到了最优的取样参数组合。该项目对革新传统组织活检取样技术、减轻病人痛苦具有非常重大的意义，技术经济和社会效益显著。共发表学术论文16篇，其中SCI收录7篇，EI收录2篇，INSPEC 收录1篇；培养博士研究生2人，硕士研究生6人；授权发明专利1项，实用新型专利2项。