Retina implant joy for blind men
Two British men who have been totally blind for many years have had part of their vision restored after surgery to fit pioneering eye implants.
They are able to perceive light and even some shapes from the devices which were fitted behind the retina.
The men are part of a clinical trial carried out at the Oxford Eye Hospital and King's College Hospital in London.
Professor Robert MacLaren and Mr Tim Jackson are leading the trial.
The two patients, Chris James and Robin Millar, lost their vision due to a condition known as retinitis pigmentosa, where the photoreceptor cells at the back of the eye gradually cease to function.
The wafer-thin, 3mm square microelectronic chip has 1,500 light-sensitive pixels which take over the function of the photoreceptor rods and cones.
The surgery involves placing it behind the retina from where a fine cable runs to a control unit under the skin behind the ear.