'Bionic' eye could restore sight in two years

A bionic eye that can restore sight to the blind could be on the market within two years say it's makers. The first six patients to try the revolutionary devices have been able to detect light, distinguish between objects and perceive direction of motion.

Millions of people around the world including the 15% or over 75 year olds affected by the macular degeneration and inherited diseases like retinitis pigmentosa may be helped by the breakthrough.

The device comes in two parts: A tiny camera in the lens or on the bridge of a pair of lightweight glasses captures images in real time. This information is transmitted to a radio receiver implanted behind the patient's ear which converts it to electrical signals that are sent to a grid of electrodes implanted in the retina. These electrodes stimulate retinal nerve cells to produce electrical impulses which send signals to the brain so that the patient can see spots of light occurring in different patterns.

Now in it's second generation, the original 'Argus' contained 16 electrodes on a 4mm by 5mm silicon and platinum chip attached to the retina. The latest Argus II containing 60 electrodes is about one quarter the size of the original, reducing surgery and recovery times.

Argus II is expected to cost around £15,000 but it's makers hope to produce a third generation implant with 1,000 electrodes, which could allow more advanced tasks such as face recognition, within seven years.