New "bionic eye" may help restore sight

A new artificial retina has been found to restore partial sight in totally blind patients.

15 patients were fitted with the vision aid, and 10 of them reported that they able to identify the direction of moving objects after a three month period. The research was presented at Neuroscience 2009, the annual meeting of the Society for Neuroscience.

"These results give new hope to the many people with degenerative retinal diseases," said Dr Jessy Dorn, lead author of the study.

The implant consists of an array of electrodes implanted on the back of the eye. It is designed to help in cases where the eye has become damaged due to age or disease. In these cases the nerve cells that detect light are destroyed and there is no known cure.

In this case, the researchers worked around the destroyed cells. Each participant was given a pair of glasses with a small video camera mounted on it, and a belt with a tiny computer attached. The computer processed video images from the camera and transmitted the data to the implanted electrodes on the retina. When the users "looked" at a monitor with a white bar sweeping across a black screen, the electrodes that corresponded with the moving bar stimulated cells in the eye, creating spots of light in their fields of vision.

"We found that most of the study participants were better able to determine the direction of the bar when using the prosthesis system than without it, or with a scrambled video input," Dr Dorn said.

"In other words, this new system gave most blind people the ability to identify an object's direction of motion -- something they could not do without it."

This article was published on Wed 21 October 2009