The Bionic Eye approaches: the next generation of Retinal Implants

Patients who have gone blind are a step closer to perhaps one day regaining some of their sight with the news that the United States FDA has approved a study to evaluate an artificial retina. Researchers at the USC Doheny Eye Institute are developing the technology that hopefully will help patients with retinitis pigmentosa and macular degeneration regain some vision using an implanted artificial retina. The announcement by Mark Humayun, professor of ophthalmology at the Keck School of Medicine of USC and associate director of research at the Doheny Retina Institute, came at a press conference at the annual meeting of the American Association for the Advancement of Science in San Francisco.

The Food and Drug Administration recently approved an Investigational Device Exemption to conduct a clinical study of the new device – dubbed the Argus II Retinal Prosthesis System.

The implantable technology is a collaborative effort between USC and Second Sight Medical Products, which manufactures the implant.

The Argus II is the second generation of an electronic retinal implant designed for the treatment of blindness due to retinitis pigmentosa, a group of inherited eye diseases that affect the retina. RP causes the degeneration of photoreceptor cells in the retina, which capture and process light, helping individuals to see. As these cells degenerate, patients experience progressive vision loss. The Argus device is essentially designed to take the place of the photoreceptors.

“The first phase of our implant work began in 2002,” Humayun said. “We have successfully implanted six patients in the trial, and we have found that the devices are indeed electrically conducting and can be used by patients to detect light or even to distinguish between objects such as a cup or plate.”

While the first generation of implants contained 16 electrodes laid out on an array, the Argus II is designed with 60 electrodes, which is intended to allow for higher-resolution images.

The new device is also approximately one quarter the size of the original, reducing surgery and recovery times.

The array is attached to the retina and used in conjunction with an external camera and video processing system to provide a rudimentary form of sight to implanted subjects.

...continued