The retina is the receptive element of the eye, similar to photographic film which captures the image formed in a camera. The retina converts images into electrical signals, which are transmitted to the brain via the optic nerve. While other portions of the eye may be transplanted or replaced with artificial implants, the retina, given its connections to the brain, is not amenable to replacement. In order to function properly, the retina must be attached properly inside the eye and have appropriate nutrition. The body is very protective of the retina and loss or breach of one of these protective functions can result in severe visual loss.