Argus II - restoring vision to the blind with microchips

25 June 2008

Work is afoot on a second generation artificial retina designed to restore vision to the blind - atleast partially. Developed through a large collaborative effort, involving biomedical researchers throughout the United States, the retinal prosthesis is an implantable electronic device intended for patients blinded by diseases such as retinitis pigmentosa and age-related macular degeneration.

These diseases destroy the light receptors in the retina, but not the nerve fibres that connect the eye to the brain. The implanted microchip stimulates the neurons in the retina, relaying visual signals that are transmitted to the chip from a tiny video camera integrated into a pair of sunglasses.

The microchip is the work of Wentai Liu, a professor of electrical engineering in the Baskin School of Engineering, University of California, Santa Cruz. For Liu, this is a major milestone in two decades of work on an artificial retina to restore vision to the blind.
 
Currently, ten patients are enrolled in a clinical trial of the device at four leading ophthalmic centres in the United States. Patients are also enrolled in trials in Mexico, Switzerland, France, and the United Kingdom.

"This chip is very different from those seen in typical electronics because it is implanted in the body and directly interfaces with a human organ. There is very little margin for error in such a system," Liu said.

The chip is a core component of the Argus II Retinal Prosthesis System, produced by Second Sight Medical Products, the commercial partner of the Artificial Retina Project funded by the US Department of Energy (DOE) Office of Science.

The DOE Artificial Retina consortium, now coordinating the project, involves three universities, six national laboratories, and a private company, Second Sight.