A Biomimetic Flexible Soft Tissue Probe for Computer Assisted Minimally Invasive Intervention

拟议的研究涉及仿生软组织探针的设计和概念验证，其灵感来自于木材钻孔黄蜂的产卵器，并应用于计算机辅助脑活检。探针将能够沿着身体内部的弯曲路径移动，但与木黄蜂的产卵器不同的是，它将置换组织（例如注射器针头）而不是移除组织（例如钻孔）。从本质上讲，仿生探针将使中空管能够准确地插入软组织深处，而不需要利用自然孔，用于任何数量的微创手术。这项可行性研究将集中在三个方面：探针的设计、驱动和控制。它还将为智能探针的进一步发展奠定基础，其中插入过程由术前图像数据交互式指导，允许以更高的准确性和可重复性访问大脑和人体其他区域的深层病变。通过精确的术前规划探针的插入点和目标点，即通过规划合适的轨迹，尽量减少两者之间的距离，同时避免大静脉、动脉、神经和其他重要结构，也可以减少由于未诊断和术后出血引起的手术并发症。计划的手术将在手术室由柔性探头在计算机辅助下执行。该项目将包括三个主要部分：1)设计一种柔性探针，能够在软组织中进行平滑的三维运动。2)设计驱动探头的驱动机构和控制策略。3)将探针和驱动机构集成为一个功能齐全的系统，适合于人工合成软组织标本的体外实验。探头设计基本上由两部分薄活检探头（直径1mm-3mm，长度约40cm）组成，两部分的往复运动将头部驱动到组织中，而不需要在底部施加任何外力；驱动单元，由三个执行器，加上控制软件和硬件组成；用于进度监控和用户交互的图形界面；并且，任选地，跟踪装置（例如，磁性跟踪器）用于实时监视探头的位置。这将需要对合适的材料、表面涂层和表面形貌进行调查，以尽量减少插入探针对周围组织的影响。为了避免任何组织损伤，还需要进一步研究合适的探针驱动方法和控制策略，以实现自动瞄准和避障。

The proposed research involves the design and proof of concept of a biomimetic soft tissue probe, inspired by the ovipositor of a wood-boring wasp, with an application to computer assisted brain biopsy. The probe will be able to be steered along curved paths within the body, but in contrast to the wood wasp's ovipositor, will displace the tissue (e.g. syringe needle) rather than removing it (e.g. drilling). In essence, the biomimetic probe will enable a hollow tube to be inserted deep into soft tissue accurately, without the need to exploit a natural orifice, for use in any number of minimally invasive procedures. This feasibility study will focus on three aspects: probe design, actuation, and control. It will also lay the foundation for the further development of an intelligent probe where the insertion process is guided interactively by pre-operative image data, allowing deep lesions of the brain and other regions of the human body to be accessed with greater accuracy and repeatability. Operative complications due to non-diagnosis and post-operative haemorrhaging could also be reduced through precise pre-operative planning of the probe's insertion and target points i.e. through the planning of a suitable trajectory that would minimise the distance between the two, whilst avoiding major veins, arteries, nerves and other vital structures. The planned procedure would be executed in the operating theatre by the flexible probe under computer assistance.The proposed project will comprise three main components:1) The design of a flexible probe capable of smooth three-dimensional motion through soft tissue.2) The design of an actuation mechanism and control strategy to drive the probe.3) The integration of the probe and the actuation mechanism into a fully functional system suitable for in vitro experimentation on synthetic soft tissue specimen.The probe design will essentially be composed of a two-part thin biopsy probe (1mm-3mm diameter, approximately 40cm in length), with the reciprocating motion of the two halves driving the head into the tissue without the need for any external force applied at the base; the drive unit, composed of three actuators, plus control software and hardware; a graphical interface for progress monitoring and user interaction; and, optionally, a tracking device (e.g. the magnetic tracker) to monitor the position of the probe head in real-time. This will require an investigation into suitable materials, surface coatings and surface topographies to minimise the impact that inserting the probe would have on the surrounding tissue. Further research will also be needed on the development of suitable probe actuation methods, in order to avoid any tissue damage, and control strategies, for automatic targeting and obstacle avoidance.