Peripheral Nerve Implementation of Functional Neuroprostheses

描述（由申请人提供）：上肢FES系统已经帮助了数百名颈椎级（即C3-C6） SCI患者使用他们的手，提高了他们的独立性和生活质量。这些系统依赖于基于肌肉的电极，特别是对于手的功能。周围神经电极已经在动物身上进行了广泛的试验，并证明了选择性刺激和安全性。与基于肌肉的电极相比，周围神经电极具有几个潜在的优势，包括完整的肌肉招募，单个植入物的多种功能，与肌肉的机械隔离，更低的刺激功率需求，以及无活动依赖性的招募。这项工作的长期目标是在几种神经假体应用中实现高选择性的神经外袖电极，特别是平面界面神经电极（FINE）。本提案的目的是评估在上肢应用中使用FINE的可行性。评估可行性的关键步骤是收集上肢神经束解剖的定量测量数据，选择最佳植入位置，选择最佳电极设计，并在术中展示这些电极刺激的选择性。这项建议包括三个具体目标。1)生成人体上肢神经的定量解剖数据。关于上肢神经的定性解剖有大量的文献，但设计电极尺寸和创建预测电极性能的计算机模拟所需的定量数据很少。2)建立上肢神经生物力学模型。一旦定量解剖可用，有限元方法（FEM）模型可以预测与袖带电极刺激招募。这提供了一个工具，以优化患者实施之前的电极设计。3)在术中试验中展示神经袖的性能。一旦电极被设计出来并通过计算机模型进行测试，对其能力的唯一真正测试就是在人体中进行测试。先前的研究表明，术中刺激选择性的测量是慢性选择性的良好预测指标。因此，急性术中试验可以证明外周神经刺激是否适合上肢神经假体系统。在完成所提出的工作后，我们期望获得所有必要的数据来证明全神经袖系统可以永久植入患者体内，以恢复中高颈椎段脊髓损伤患者的上肢功能。我们希望这项工作将对上肢FES的应用产生重大影响，并为其他应用铺平道路，例如截肢假肢的神经接口。

DESCRIPTION (provided by applicant): Upper extremity FES systems have assisted hundreds of individuals with cervical-level (i.e. C3-C6) SCI to use their hands and increase their independence and quality of life. These systems have relied on muscle-based electrodes, especially for the functions of the hand. Peripheral nerve electrodes have been extensively tested in animals and demonstrated selective stimulation and safety. Peripheral nerve electrodes offer several potential advantages compared to muscle-based electrodes, including complete muscle recruitment, multiple functions from a single implant, mechanical isolation from the muscle, lower stimulation power requirements, and no activitydependent recruitment. The long-term goal of this work is to implement highly selective, extraneural cuff electrodes, specifically the flat interface nerve electrode (FINE) in several neuroprosthesis applications. This purpose of this proposal is to assess the feasibility of using the FINE in upper extremity applications. The key steps in assessing feasibility are to collect quantitative measures of the fascicular anatomy of the upper extremity nerves, to select optimal implant locations, to select optimal electrode designs, and to demonstration intraoperatively the selectivity of stimulation with these electrodes. The proposal consists of three specific aims. 1) Generate quantitative anatomical data of the human upper extremity nerves. There is extensive literature on the qualitative anatomy of the upper extremity nerves, but little quantitative data required to design electrode sizes and create computer simulations for prediction electrode performance. 2) Develop neurobiomechanical models of upper extremities. Once the quantitative anatomy is available, finite element method (FEM) models can predict recruitment with cuff electrode stimulation. This provides a tool to optimize the electrode design prior to patient implementation. 3) Demonstrate nerve cuff performance in intraoperative trials. Once an electrode is designed and tested via computer models, the only true test of its capabilities is by testing in humans. Previous studies have shown that intraoperative measures of stimulation selectivity are good predictors of chronic selectivity. Therefore, acute, intraoperative testing can demonstrate whether or not the peripheral nerve stimulation is appropriate for upper extremity neuroprostheses systems. At the completion of the proposed work, we expect to have all the necessary data to show that an all-nerve cuff system can be permanently implanted in a patient to restore upper extremity function in mid- to high-cervical level SCI patients. We expect this work will make a significant impact in upper extremity FES applications and pave the path to other applications, such as neural interfaces for amputee prosthetics.