Optically Actuated Needles for Oncological Applications

描述(由申请人提供)：在FastTrack第一阶段/第二阶段SBIR申请中，IFOS与斯坦福设计研究中心(CDR)合作，提议开发和验证一种用于精确成像辅助经皮手术的主动转向、光驱动、小口径针头。这项创新特别针对针对深层组织的手术中精确放置针头的需求，在这些程序中，由于解剖障碍和避开重要器官的需要，进入路径受到限制。所提出的主动转向可以补偿在将针插入软组织时遇到的偏转，随着通向目标的路径的延长，偏转变得越来越重要。这种偏离计划的路径可能会导致多次重新插入，增加患者的不适感和手术时间，并影响微创手术的有效性。主动转向概念是基于嵌入在柔性针头中的形状记忆合金(SMA)的光学激活。将采用与标准针尖和外套管护套兼容的设计特征。与其他基于电或磁驱动的技术不同，该方法与包括MRI在内的所有主要成像技术都兼容。通过使用光纤连接，从激光电源到针头的距离可以大于肌腱接近所需的驱动马达的距离。这项技术需要最小的功率输入，并且可以在用户友好的手持式活检针系统中实现。虽然基本的针头概念不依赖于复杂的算法和机器人的针头插入系统，但基本的设计包括一个流线型的后端，可以随时连接到更复杂的仪器，包括先进的在线成像接口功能。在以前的工作中，已经在模仿人类前列腺组织特性的模体中重复地实现了超过2�/秒的弯曲速度。此外，周围组织的间接温升也很小，有效地消除了人们对热损伤的担忧。第一阶段的工作旨在展示在体外前列腺组织中使用各种针插入策略的更大偏转效率，使用一种涉及低转变温度SMA和优化的超弹性活检针结构和对照的新方法。这项工作将导致第二阶段的进一步开发活动，包括更细的针头设计，控制台设计，以及能够实时测量针头曲率和原位组织反作用力的闭环控制系统。在第二阶段，我们还将研究转向方案，这些方案将利用轴向旋转和其他已知的被动控制策略，从而为针系统增加弯曲自由度和灵活性。这些研究将在一系列体内实验中达到高潮，目标是在超声和核磁共振等成像手段下进行前列腺活检和近距离放射治疗，以建立关键的临床疗效和安全参数，并验证实用/临床方面的便利，以促进FDA的批准和将新的有源针头成功引入最终用户。

DESCRIPTION (provided by applicant): In this FastTrack Phase I/II SBIR application, IFOS, in collaboration with the Stanford Center for Design Research (CDR) proposes to develop and validate an actively steered, photo-actuated, small-caliber needle for precise imaging-assisted percutaneous procedures. This innovation specifically addresses the need for precise needle placement in procedures targeting deep tissue, where routes of entry are restricted due to anatomical obstructions and the need to avoid vital organs. The proposed active steering can compensate for the deflection encountered during needle insertion into soft tissue, which becomes increasingly significant as the path to the target lengthens. Such deviations from the planned path can result in multiple reinsertions, adding to patient discomfort and procedure time, and compromising the effectiveness of minimally invasive procedures. The active steering concept is based on optical activation of a shape memory alloy (SMA) embedded within a flexible stylet. Design features compatible with standard needle tips and outer cannula sheaths will be employed. Unlike other techniques based on electrical or magnetic actuation, the proposed approach is compatible with all major imaging techniques, including MRI. By using fiber-optic connections, the stand-off distance from the laser power source to the needle can be greater than that for actuation motors required for tendon approaches. The technique requires minimal power input and can be implemented in a user-friendly hand-held biopsy needle system. While the basic needle concept does not rely on complex algorithms and robotic needle insertion systems, the basic design includes a streamlined back-end that affords a ready connection to more complex instrumentation, including advanced online-imaging interface capabilities. In prior work, bending rates of over 2� per second have been repeatably achieved in phantoms that mimic the properties of human prostate tissue. Also, the collateral temperature rise in surrounding tissue was shown to be minimal, effectively eliminating thermal damage as a concern. The Phase I effort is designed to demonstrate still greater deflection efficiency using various needle insertion strategies in ex vivo prostate tissue, using a novel approach involving low-transition-temperature SMAs and optimized superelastic biopsy needle structures and control. This work will lead to further development activities in Phase II, including thinner needl designs, a console design, and a closed-loop control system that enables real-time needle curvature and in situ tissue reaction force measurements. In Phase II, we also will investigate steering protocols that would take advantage of axial rotation and other known passive control strategies, thereby adding bending degrees-of freedom and dexterity to the needle system. These studies will culminate in a series of in vivo experiments, targeting prostate biopsy and brachytherapy procedures under imaging modalities such as ultrasound and MRI, to establish key clinical efficacy and safety parameters, and validate practical/clinical aspects for facilitatig FDA approval and the successful introduction of the new active needle to end users.