[Review of visual prosthesis (II)--cortical visual prosthesis, optic nerve prosthesis and vision substitution devices].

Cortical visual prosthesis, optic nerve visual prosthesis and vision substitution devices are alternative ways for repairing the visual impairment in case of optic nerve injury, retina lose or blindness without fully developed central visual system. This article is a state-of-art review of the principles, technical details and the limitations of different types of prostheses beyond the retinal prosthesis.