Degenerations of the outer retina are hereditary diseases leading to significant loss of vision. Several concepts of active electrical stimulation of the remaining retinal network resulted in the development of retinal visual implants and prosthetic vision. Subretinal and epiretinal visual implants are currently the leading approaches in restoring functional vision in blind humans with retinitis pigmentosa or other outer retinal degenerations. This review gives a short overview about the principles, advantages, limitations and vision outcome of the up-to-date published artificial vision by electronic visual implants, as well as their known biocompatibility and safety issues.

Keywords:
Neuroprosthetics, Hereditary retinal degenerations, Retinal implants, Artificial vision, Retinitis pigmentosa, Subretinal implant, Epiretinal implant
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2013
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