An implantable epiretinal device for near-infrared light perception

Abstract

Human vision relies on photoreceptor cells in the outer retina that are sensitive to visible light. However, many people suffer from blindness due to retinal diseases that cause photoreceptor degeneration. Electrical stimulation of retinal neurons can recreate the action potentials associated with seeing that are generated by these cells. Here we report a thin artificial retina that can be adhered to the epiretinal surface and can convert near-infrared (NIR) light into electrical stimuli that selectively stimulate ganglion cells. The artificial retina consists of a NIR-sensitive phototransistor array and three-dimensional liquid metal micropillar electrodes. The liquid metal electrodes enhance proximity to retinal ganglion cells, providing effective charge injection while minimizing tissue damage, owing to their low Young's modulus. Ex vivo studies demonstrate its biocompatibility, and in vivo studies using healthy and blind mice demonstrate perception of both visible and NIR light, as indicated by cortical recordings and behavioural tests. The retina could, in the future, be used to create a NIR visual channel in patients with photoreceptor degenerative blindness without interfering with their remaining natural vision.