Single-pixel epiretinal stimulation with a wide-field and high-density retinal prosthesis for artificial vision

Retinal prostheses hold the promise of restoring artificial vision in profoundly and totally blind people. However, a decade of clinical trials highlighted quantitative limitations hampering the possibility to reach this goal. A key obstacle to suitable retinal stimulation is the ability to independently activate retinal neurons over a large portion of the subjects visual field. Reaching such a goal would significantly improve the perception accuracy in the users of retinal implants, along with their spatial cognition, attention, ambient mapping and interaction with the environment. Here we show a wide-field, high-density and high-resolution photovoltaic epiretinal prosthesis for artificial vision. The prosthesis embeds 10,498 physically and functionally independent photovoltaic pixels allowing for both wide retinal coverage and high-resolution stimulation. Single-pixel illumination reproducibly induced network-mediated responses from retinal ganglion cells at safe irradiance levels. Furthermore, the prosthesis enables a sub-receptive field response resolution for retinal ganglion cells having a dendritic tree larger than the pixels pitch. This approach could allow the restoration of mid-peripheric artificial vision in patients with retinitis pigmentosa.