Retinal implant raises hope for restored vision

U.S. Food and Drug Administration approved the initiation of clinical trial of a technology that researchers hope can help blind people regain some of their sight.

A new electronic artificial retina is meant to partially restore useful vision to people who have lost theirs due to degenerative eye conditions such as retinitis pigmentosa or macular degeneration.

While, ‘retinitis pigmentosa’ is an inherited disorder in which abnormalities of the photoreceptors (rods and cones) or the retinal pigment epithelium (RPE) of the retina lead to progressive visual loss.
By contrast, macular degeneration is a medical condition in which the light sensing cells in the macula malfunction and, over time, cease to work.

The device -- known as the Argus II Retinal Prosthesis System consists of an array of electrodes implanted on the back of the retina, a digital camera worn on the user's body, and a transmitter/image processor that converts the image to electrical signals and beams them to the electrode array in the eye.

A collaborative effort between researchers at the University of Southern California (USC), Doheny Eye Institute and Second Sight Medical Products, which manufactures the implant, the technology is an updated and more powerful version of its original design.

Originally, the artificial retina used an array of 16 electrodes which were surgically inserted into the infected eye for treatment of damaged retinal photoreceptor cells.

Whereas, the second generation retinal prosthesis have been fitted with 60 electrodes that researchers claim will offer higher-resolution sight.

Also, compact in design- approximately one quarter the size of the original, the news device reduces surgery and recovery times.

Expressing enthusiasm about the new device, Dr. Mark Humayun, professor of ophthalmology, Doheny Eye Institute in the Keck School of Medicine, University of Southern California, San Francisco and lead researcher said, “Our work to date with our retinal prosthesis has exceeded all expectations we had, and we are very excited and look forward to the results from our 60-channel implant.”

“The clinical trials of the newest generation of retinal prosthesis will begin later this year”, Humayun added.

Prof. Humayun said people who are blind from birth will not be able to get any benefit from this device but it will work for those people who had vision but lost it later.