Bionic eye allows blind man to 'see' first time in 33 years

A revolutionary new bionic eye implanted into a 66-year-old blind man in the US has allowed him to 'see' for the first time in 33 years.

Larry Hester was diagnosed with retinitis pigmentosa when he was in his early 30s. At the time, the degenerative disease that would rob his sight was poorly understood, and there were no known treatments, researchers said.

On October 1, 2014, Hester became only the seventh person in the US to have a so-called bionic eye - an Argus II Retinal Prosthesis Device - activated as a visual aid to send light signals to his brain.

The device incorporates technology initially developed by researchers at the Duke Eye Centre; its sophisticated features were further enhanced and marketed by a company called Second Sight Medical Products.

Using wireless technology, a sensor is implanted in the eye to pick up light signals sent from a camera mounted on special eyeglasses.

Paul Hahn, a retinal surgeon at the Duke Eye Centre, implanted the sensor on September 10, and activated the device three weeks later - to the sheer delight of Hester and his family.

Hahn cautioned that the device will not restore normal eyesight, but instead provide a visual aid that could help Hester distinguish a door from a wall, or a crosswalk painted in a roadway.

Hester describes seeing flashes of light that are more intense when he aims the camera at lights or light-coloured objects.

During a clinic visit, Hester described "seeing" sights he had long believed were past memories - a white duck swimming in a pond, the harvest moon, his wife's yellow chrysanthemums.

Hester's wife, Jerry, said her most cherished moment came while they were watching a football game. She was sitting in a dark chair, and her skin was enough of a contrast that Hester could see flashes. He reached out and touched her face.