Fundamental Properties of Micromagnetics for Peripheral and Central Nervous System Stimulation

周围和中枢神经系统刺激的微磁学的基本特性

• 批准号: 1202235
• 负责人: Gianluca Lazzi
• 金额: $ 38.17万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1202235&HistoricalAwards=false
• 关键词: Fundamental; Properties; Micromagnetics; Peripheral; Central

Recent neuroengineering research has demonstrated that motor function and sensing in patients that are affected by neurodegenerative diseases can be partially restored by means of electrical neurostimulation. However, electrode arrays currently used to replace endogenous electrical activation present several drawbacks, including exposure of metal contacts to conductive tissue, potential need for excessive charge density to achieve stimulation when electrode size is small, and lack of tolerance with respect to imperfect contact between the electrode contacts and the neural tissue.The PIs have recently demonstrated that a new class of microcoils can effectively stimulate the peripheral nervous system, leading to the idea that magnetic microstimulators for implantable devices and neuroprostheses can be devised. Since the mechanisms of magnetic stimulation are centered on eddy currents and their gradients, coils do not need direct contact with the tissue and therefore they can be completely insulated, thus avoiding the possibility of material reactions with conductive neural or surrounding tissues. Further, arrays of coils can potentially offer more options to control the shape of the induced magnetic fields, and therefore eddy currents, and their operation is not affected by contact capacitance. Intellectual Merit: The goals of the proposed work capitalize on our theoretical and experimental findings that contact magnetic stimulation of the nervous system is feasible, and investigate new classes of microcoils and magnetic stimulators that will be particularly suited for micromagnetic stimulation. Specifically, a major goal is to investigate coil geometries that allow control of the microcoil?s magnetic fields; this will increase the magnetic flux density levels well beyond those of traditional coils and alter the orientation of the fields in the proximity of the target neurons. Ferrite-backed microcoil arrays have the potential to provide increased field strength, sharp gradients, and control of the magnetic field needed for selective neurostimulation. In this work, the PIs investigate novel devices that could provide a paradigm shift compared to traditional electrical neurostimulators. Broader Impacts: This work has the potential to offer a highly innovative solution to peripheral and central system neurostimulation devices. Providing an alternative solution to surface or penetrating electrodes could positively impact a number of implantable systems, which currently suffer from the significant drawbacks of electrical neural stimulation. Besides the important clinical impact, the proposed program offers unique opportunities to train engineering students in a highly interdisciplinary activity at the forefront of engineering technology and medical research. In addition to utilizing the proposed research activity in various existing programs designed to have a lasting impact on current and prospective undergraduate students, the proposed project will increase the interest of engineering students in the emerging field of neuroprosthetics and demonstrate the benefits of engineering to medicine. The PIs will provide additional learning opportunities targeted at K-12, 2-year, and 4-year feeder schools and colleges through outreach programs.

最近的神经工程研究表明，受神经退行性疾病影响的患者的运动功能和感知可以通过电神经刺激部分恢复。然而，目前用于替代内源性电激活的电极阵列存在几个缺点，包括金属触点暴露于导电组织，当电极尺寸小时，可能需要过度的电荷密度来实现刺激，以及对于电极触点和神经组织之间的不完美接触缺乏耐受性。PI最近已经证明，一类新的微弹簧圈可以有效地刺激周围神经系统，导致的想法，磁微刺激器的植入装置和神经假体可以设计。由于磁刺激的机制以涡流及其梯度为中心，线圈不需要与组织直接接触，因此它们可以完全绝缘，从而避免与导电神经或周围组织发生材料反应的可能性。此外，线圈阵列可以潜在地提供更多的选择来控制感应磁场的形状，并且因此控制涡电流，并且它们的操作不受接触电容的影响。智力优势：所提出的工作的目标利用我们的理论和实验发现，接触磁刺激神经系统是可行的，并调查新的类别的微线圈和磁刺激器，将特别适合于微磁刺激。具体来说，一个主要目标是调查弹簧圈的几何形状，允许控制的微弹簧圈？s磁场;这将使磁通量密度水平增加到远远超过传统线圈的水平，并改变目标神经元附近的场的方向。铁氧体背衬微弹簧圈阵列有可能提供选择性神经刺激所需的增强场强、锐梯度和磁场控制。在这项工作中，PI研究了与传统电神经刺激器相比可以提供范式转变的新型设备。 更广泛的影响：这项工作有可能为外周和中枢系统神经刺激器械提供高度创新的解决方案。为表面或穿透电极提供替代解决方案可以积极地影响许多可植入系统，这些系统目前遭受电神经刺激的显著缺点。除了重要的临床影响，拟议的计划提供了独特的机会，培养工程专业的学生在工程技术和医学研究的前沿高度跨学科的活动。除了在现有的各种项目中利用拟议的研究活动，旨在对当前和未来的本科生产生持久的影响外，拟议的项目还将提高工程专业学生对新兴神经修复学领域的兴趣，并展示工程对医学的好处。PI将通过推广计划为K-12，2年制和4年制的支线学校和学院提供额外的学习机会。