Artificial Retina Device Containing 240 Densely-packed Electrodes Packaged Into A Chronic, Wireless System

摘要

Purpose: : Millions suffer from blindness due to damaged photoreceptors. Microfabrication technologies allow for the development of devices that bypass damaged cells and directly stimulate the optic nerve. We developed an epi-retinal prosthesis consisting of a high-density electrode array that electrically stimulates ganglion cells. We report a new 240-electrode, wireless device that is packaged for chronic implantation. This work was done in collaboration with the Department of Energy Artificial Retina Team, including Second Sight Medical Products and Doheny Eye Institute. Methods: : The Artificial Retina system contains: 1) An external camera and controller, and 2) An implant with electronics. The implanted system consists of an epi-retinal, polymer electrode array that is tacked to the retina. The electrodes are powered by electronics encapsulated in a biocompatible package. The implant is wirelessly activated by the external controller. We fabricated the high-density electrode arrays and interconnects on flexible substrates. The arrays were coated with silicone and contoured to the shape of the eye. The array was electrically connected to the package, which consists of electrical components for wireless telemetry, signal processing, and electrical stimulation. Surgical implantation tools were developed to tack the array to the retina. Results: : The epi-retinal implant consisting of a 240-electrode array and package was successfully microfabricated and tested. Each electrode on the array was verified as electrically functional. Individual electronic components were verified, assembled into the package, and validated. The prosthesis was implanted in multiple animals with 200+ verified working electrode sites before and after surgery. Conclusions: : We successfully demonstrated: 1) Design, fabrication, and testing of high-density polymer electrode arrays for epi-retinal stimulation, 2) Assembly, packaging, and testing of electronics, and 3) Encapsulation with biocompatible materials for long-term implantation. This device is a 4x increase in electrode count and density over the previous 60-electrode design (ArgusTM II, Second Sight Medical Products), while maintaining approximate device size.