Floating Micro-Stimulators for Neural Prosthetics

描述（由申请人提供）：几十年来，外周和中枢神经系统的电激活已经被研究用于治疗神经疾病，许多设备已经成功进入临床阶段。人工耳蜗、脊髓损伤时用于膀胱和肠道控制的骶神经根刺激、癫痫时用于迷走神经刺激是这类设备的一些众所周知的例子，每年都有成千上万的患者被植入这种设备。阻止或阻碍许多其他神经假体装置实施的主要障碍是刺激电极与神经组织的机械不匹配以及导致组织损伤的电线连接的系缚。电刺激器的远程控制，没有相互连接，足够小，以达到良好的空间选择性，以最小的替代神经组织是非常需要的。我们建议开发非常小（大约200微米）的光伏元件，可以植入脊髓或大脑皮层，并使用近红外激光束从硬脑膜外通过神经组织激活。这些浮动光激活微型电刺激器（flame）的几何形状和界面特性将被优化，以最大限度地将能量传递到组织中，同时最小化设备尺寸。将设计各种尺寸的设备以满足不同神经刺激应用的要求。优化后的flame的刺激特性将在培养基（琼脂/生理盐水）和体内（大鼠）中进行测试。未来的设计将包括火焰的高级版本，它可以针对不同波长的光进行调整，以选择性激活。光通信的硅技术已经得到了广泛的发展和研究，并且可以通过合理的研究进行神经刺激。一些直接的应用包括但不限于视觉和听觉皮层刺激替代这些感觉，以及腰骶脊髓微刺激用于脊髓损伤中的膀胱控制和运动。

DESCRIPTION (provided by applicant): Electrical activation of the peripheral and central nervous system has been investigated for treatment of neural disorders for many decades and a number of devices have already moved into the clinical phase with success. Cochlear prostheses, sacral root stimulation for bladder and bowel control in spinal cord injury, and vagus nerve stimulation in epilepsy are some of the well-known examples of such devices that are being implanted in thousands of patients every year. A major obstacle that has been preventing or otherwise impeding the implementation of many other neural prosthetic devices is the mechanical mismatch of the stimulation electrodes with the neural tissue and the tethering of the wire connections that result in tissue trauma. Electrical stimulators that are remotely controllable with no interconnects and sufficiently small so that a good spatial selectivity is achieved with minimal replacement of the neural tissue are greatly needed. We propose to develop very small (approximately 200 um) photovoltaic elements that can be implanted into the spinal cord or the brain cortex and activated from outside the dura mater through the neural tissue using near infrared laser beams. The geometry and the interface properties of these floating light activated micro electrical stimulators (FLAMES) will be optimized for maximum transfer of energy into the tissue while minimizing the device size. Devices with various sizes will be designed to meet the requirements of different neural stimulation applications. The stimulation properties of the optimized FLAMES will be tested in medium (agar/saline) and in vivo (rat). Future designs will include advanced versions of the FLAMES that are tuned for different wavelengths of light for selective activation. The silicon technology of optical communication has already been developed and studied extensively and can be modified for neural stimulation with reasonable amount of research. Some of the immediate applications include but not limited to visual and auditory cortex stimulation for substitution of these senses, and micro-stimulation of the lumbo-sacral cord for bladder control and locomotion in spinal cord injury.