An Italian research team, from the Italian Institute of Technology in Genoa, has shown that a photovoltaic polymer can restore light-sensing capabilities to damaged retinas, offering hope of a simple way to restore vision to many people with degenerative eye diseases such as age-related macular degeneration.
This type of polymer, which converts light into an electronic signal, does not require the power supply that's been necessary with other types of artificial prosthetics. To achieve this result, the researchers used a poly 3-hexylthiophene organic film to encourage neural stimulation through photo-sensitization.
"Organic polymers could form the basis for the next generation of retinal prostheses as they are both thin and flexible" says Stephen Rose, chief research officer at the Foundation Fighting Blindness.
Tests on the artificial retina were carried out in daylight levels of brightness, indicating the technology's strong potential for being used in prosthetics. For now, however, the polymer films which have been tested did not respond to the full range of light sensitivity that normal photoreceptors can handle. The researchers are confident that it is not an insurmountable obstacle and that it could quite easily be overcome.
Given these encouraging results, scientists have already begun testing polymer-based retinal implants in rats with retinitis pigmentosa.