This is Sheila Irvine, she's one of 38 patients in five countries who have taken part in a trial which uses an implanted microchip to restore sight in people with an eye disease which causes blindness.

She has geographical atrophy, a form of AMD which is a slow deterioration of the cells of the eye's macula which is responsible to giving detailed central vision.

Over the years these light-sensitive retinal cells die.

There is no current treatment for this disease which affects 5 million people around the world according to the trial's researchers.

Their study is published in the New England Journal of Medicine.

Irvine says she was distraught when she discovered she was losing her sight.

She says: "The worst day was I sent my driver's license back, I'd always had a scooter, a motorbike and a car always, and I cried all day long that day and then I said, no more. Now move on and get on with things."

All the participants in the trial had only poor peripheral vision left.

The procedure involves removing some of the eye’s vitreous jelly to make room for the chip which is inserted by a surgeon.

The ultra-thin microchip just 2mm x 2mm and looks like a telephone SIM card.

It's inserted under the centre of a patient’s retina.

After surgery the patient uses augmented-reality glasses, containing a video camera connected to a small computer, with a zoom feature to enlarge the text.

Researchers say the device was able to restore some form of sight in over 80% of trial participants.

They could also read, on average, five lines of a vision chart whereas before they couldn't even see the chart.

The leader of the trial Mahi Muqit is consultant ophthalmic surgeon at Moorfields Eye Hospital in London.

He explains: "The microchip is an array of solar panels that's activated by light, so the patient puts on a pair of goggles, it has a video camera which captures visual scenes so for example, a book, the letters and words are then projected by the camera onto the chip wirelessly by infrared light and it's all instantaneous."

"So images reach the chip, images then go back to the glasses, the images are refined and enhanced and then they go back to the chip, processed through the remaining retina the inner part travels down the optic nerve up to the brain. So essentially when the patient puts on the glasses, this instantly all happens," says Muqit.

Other eye prosthetics have been developed in the past but Muqit says none has achieved as much as the PRIMA device which was the subject of the study in NEJM.

He says: "After the implantation it takes about several months for them to understand this new vision, but the most important thing with this device which has never been demonstrated before with any device is that patients can see what we can see."

The chip is activated about a month after the surgery has time to settle.

Artificial intelligence (AI) algorithms through the pocket computer process information taken from the camera, this is converted into an electrical signal.

This signal passes through the retinal and optical nerve cells into the brain, where it is interpreted as vision.

The patient uses their glasses to focus and scan across the main object in the projected image from the video camera.

Sight doesn't come straight away, Irvine remembers her intensive training before she began to decipher letters and then words, a joy for someone who loved books.

"Most of all, to stay independent is a big thing for anybody, but my love before this, I was an avid bookworm and I want to read, so it's in me I think you know, and when I was given a book I couldn't see it at all. It was like getting a cloud down and putting it on the page. It was just white and one day I start to see edges on there. Here we go, here we go now. They were giving letters and I was doing it quick as lightning and I was getting excited, it's meant to be," says Irvine.

Researchers are hoping the study will help them to further develop the device.