Validation of a Foldable and Photovoltaic Wide-Field Epiretinal Prosthesis

Inspired by intra ocular lenses, we designed a foldable and wide-field epiretinal prosthesis capable of achieving a wireless photovoltaic stimulation of retinal ganglion cells with a remarkable increase in its retinal coverage and in the number of stimulating pixels. Within a visual angle of 46.9 degrees, it embeds 2215 stimulating pixels, of which 967 are in the central area of 5 mm. It is foldable to limit the scleral incision during implantation and it has a hemispherical shape to remain in tight contact with the retina. We also demonstrate that the prosthesis is not cytotoxic, while accelerated ageing shows a lifetime of at least 2 years. Moreover, it fulfills optical and thermal safety requirements. Last, the flexibility of the fabrication process may allow the production of a hemispherical prosthesis adjusted to the real eye curvature of the patient. These advances provide a solution towards the improvement of both visual acuity and visual field in blind patients.