A new bionic eye, Argus II Retinal Prosthesis System developed by Second Sight Medical Products, is set to enable blind people suffering from a group of conditions called retinitis pigmentosa to read letters and simple words.
The device includes a small video camera, a transmitter mounted on a pair of eyeglasses, a video processing unit (VPU) and an implanted retinal prosthesis (artificial retina).
The VPU transforms images from the video camera into electronic data that is wirelessly transmitted to the electrodes, which transform the data into electrical impulses that stimulate the retina to produce images.
A clinical trial to test the safety and effectiveness of the Argus II device has been running at Moorfields Eye Hospital in London, and at other sites internationally.
The hospital has recruited seven patients in the trial.
A majority of patients in the trial were able to consistently identify large letters, however a smaller group was able to read two and three-letter words.
The implants are not suitable for patients suffering from glaucoma, age-related macular degeneration or trauma to the eye caused by accidents.
The Argus II implant received the CE mark in March 2011 and the US Food and Drug Administration in February 2013.
The implant is not yet available in the UK on the National Health Service, although available in private sector.