Power and Data Telemetry System for a 256-Channel Retinal Implant

描述（由申请人提供）： 该提案的目的是为新一代密封式微型神经刺激器开发电力和数据遥测系统，该刺激器适合于长期植入患者眼睛， 治疗视网膜变性疾病。这些视网膜假体必须非常小，以便植入眼睛外部，因此不包含电池。这些设备将从患者戴在眼镜上的相机接收图像数据。来自外部电池的电力和来自外部相机的数据都将无线传输到假体。这是通过在假体植入线圈附近放置外部线圈来完成的。向外部线圈输送正弦电流会产生磁场，在植入线圈中感应电压。这些正弦电流可以被调制以编码数据。过去我们和其他人开发的视网膜假体已经实现了16到60个独立的刺激通道或像素。VA创新视觉康复中心（CIVR）致力于建立一个至少有256个通道的视网膜假体，用于未来的临床试验。这样的设备将需要更多的传输功率来支持大的 通道数量，以及更高的数据传输带宽，以提供附加的刺激信息。该提案旨在开发这种下一代遥测系统。此外，由于这种假体是用于人类，我们优化的遥测系统将包括新的安全功能。它将实现双向遥测，向外部控制器发送信息，描述植入物的功能、刺激电极的波形和植入物电源的测量值。其中第一个将用于确保植入物正常工作，在接收数据时没有故障或错误。第二个将用于监测电极的电化学状态，以确保它们不会随时间发生显著变化。第三条信息，植入物电源的测量，将用于调整电力遥测系统，以提供恰到好处的电力。功率太小会使植入物功能不正常，太大会导致不必要的散热，甚至损坏设备。最终的电力和数据遥测系统将被纳入我们的下一代256通道视网膜假体中，该假体将被封装在由CIVR团队的其他成员开发的最先进的钛包中。这些假体将由CIVR的手术团队在尤卡坦小型猪试验中进行测试。在那之后，我们计划进入人体临床试验，希望这种设备能够在临床上为盲人所用。这种256通道的设备可能与这种优化的遥测系统，预计将开辟了VA和盲人退伍军人新的康复可能性，通过更具体的，有针对性的神经刺激比以前可能-特别是恢复真正有用的视力盲人患者，但也在其他领域的医学，如深部脑或脊髓刺激。总之，我们希望我们所服务的盲人群体最终将受益于我们创造复杂的、高度生物稳定的视网膜神经刺激器的能力所带来的视力改善;此外，预计未来所有类型的无线植入式假体的通道容量和功效都将得到改善。

DESCRIPTION (provided by applicant): The aim of this proposal is to develop power and data telemetry systems for a new generation of hermetic miniaturized neural stimulators suitable for chronic implantation in a patient's eye to treat degenerative diseases of the retina. These retinal prostheses will necessarily be very small in order to be implanted onto the outside of the eye, and will therefore contain no battery. The devices will receive image data from a camera worn by the patient on a pair of glasses. Both power from an external battery and data from the external camera will be transmitted wirelessly to the prosthesis. This is done by placing an external coil near the implanted coil of the prosthesis. Delivering sinusoidal current to the external coil creates a magnetic field that induces a voltage in the implanted coil. These sinusoidal currents can be modulated to encode data. Retinal prostheses developed in the past by our group and others have implemented between 16 and 60 independent stimulating channels, or pixels. The VA Center for Innovative Visual Rehabilitation (CIVR) strives to build a retinal prosthesis with at least 256 channels for future clinical trials. Such a device will require both more transmitted power to support the large number of channels, and a higher data transmission bandwidth to supply the additional stimulation information. This proposal aims to develop this next-generation telemetry system. Additionally, since this prosthesis is meant for use in humans, our optimized telemetry system will include new safety features. It will implement bidirectional telemetry to send information to the external controller describing the function of the implant, waveforms from the stimulating electrodes, and measurements from the implant's power supplies. The first of these will be used to ensure that the implant is working properly, with no malfunctions or errors in receiving data. The second will be used to monitor the electrochemical status of the electrodes to ensure they are not changing significantly over time. The third piece of information, measurements of the implant's power supplies, will be used to adjust the power telemetry system to deliver just the right amount of power. Too little power can make the implant function improperly, and too much can cause unnecessary heat dissipation and even damage to the device. The final power and data telemetry system will be incorporated into our next-generation 256-channel retinal prosthesis, which will be enclosed in the state-of- the-art titanium package being developed by other members of the CIVR team. These prostheses will be tested by the surgical team of the CIVR in Yucatan minipig trials. After that, we plan to enter clinical trials in humans with the hop that this device will become clinically available to the blind. This 256-channel device made possibly with this optimized telemetry system is expected to open up to the VA and to blind veterans new rehabilitative possibilities through more specific, targeted neural stimulation than has previously been possible- especially for the restoration of truly useful vision to blind patients, but also in other areas of medicine such as deep brain or spinal cord stimulation. In sum, it is our hope that the blind population we serve will ultimately benefit from the improved visual acuity that will arise from our ability to create complex, highly biostable retinal neurostimulators; additionally, the channel capacity and efficacy of future wireless implantable prostheses of all types is expected to be improved.