Researchers developing new prosthetic retina

Last week saw the development of a light powered bionic eye that using infra red light powered a retinal implant could help the visually impaired. While this technology improved on existing retinal implants, Scottish researchers are now developing a revolutionary new contact lens that would be able to help sufferers of the degenerative eye disease known as age related macular degeneration or AMD.

The Scottish researchers from the Strathclyde University in Glasgow working alongside with researchers from Stanford University in the United states are developing a prosthetic retina aiming to combat AMD that at present affects one in 500 patients aged between 55 and 64 and one in eight aged over 85. The new device will be different from existing ones in that it will be made of silicon and will be wireless and according to the researchers, easier to implant.

Commenting upon the project, lead researcher, Dr Keith Mathieson of Strathclyde University said, “AMD is a huge medical challenge and, with an aging population, is continuing to grow. The prosthetic retina we are developing has been partly inspired by cochlear implants for the ear but with a camera instead of a microphone and, where many cochlear implants have a few channels, we are designing the retina to deal with millions of light sensitive nerve cells and sensory outputs. The implant is thin and wireless and so is easier to implant. Since it receives information on the visual scene through an infra-red beam projected through the eye, the device can take advantage of natural eye movements that play a crucial role in visual processing."

AMD if left untreated often leads to blindness and it is often seen that while not affecting the neurons in the eye, AMD does affect the photoreceptors of the eye, the cells responsible for capturing images. But the new prosthetic retina will try to capitalize on this fact by electrically stimulating the intact neurons of the eye, restoring some vision. Much like the aforementioned light powered bionic eye, the prosthetic retina too will be powered by a similar means, using a pair of video goggles to transmit infra red power to the prosthetic retinas power and images but unlike existing means to power the lenses, the new prosthetics lenses are powered by pulsed near infra red light, that eliminates the need for surgery and implantation, being described as "simpler in design and operation than existing models"

While the prosthetic lenses are still under development, details as to their construction and function are given in the latest edition of the journal, nature Photonics.

(http://www.bbc.co.uk/news/uk-scotland-glasgow-west-18103242)