Bionic eye promises to restore sight to the blind

A team of eye specialists at London's Moorfields Eye Hospital ave fitted "bionic eyes" to two men in their 50s to partially restore their eyesight.

The 'bionic eye' is an artificial eye, connected to a camera on a pair of glasses, developed by the American firm Second Sight; patients wear a small unit at their waist to power the camera and process the images.

This is the first time the treatment has been tried on patients in the UK and is part of an international clinical study on the therapy.

Experts warn that though the technique is exciting and may restore a basic level of vision, it is still early days.

The trial is testing the bionic eye on people who have become blind through retinitis pigmentosa, an inherited eye disease that affects the retina.

The disease is progressive and affects as many as 25,000 in the UK and is usually diagnosed in childhood and over a number of years people become blind.

The eye surgeon who carried out the 3 hour operations, Dr. Lyndon da Cruz, says the devices, tiny metal plates studded with electrodes, were successfully implanted into the retina at the back of the eye and both patients and are now recovering well.

To what extent the bionic eye will improve vision remains to be seen and it is expected that only light and dark outlines will be discernable - it will take the men a few months to learn to use the system.

The bionic eye, which is called Argus II, works via the camera to transmit a wireless signal to an ultra-thin electronic receiver and electrode panel that are implanted in the eye and attached to the retina.

The electrodes stimulate the remaining retinal nerves allowing a signal to be passed along the optic nerve to the brain.

The two British men are among 15 patients given the artificial retinas as part of a three-year trial in the U.S., Mexico and Europe.

To date the U.S. trials have been successful in restoring a certain amount of vision; the bionic eyes which cost £15,000 could be approved for general use within three years.

Dr. da Cruz says three more patients will soon receive the treatment and along with five more provided there are no complications.