Researchers at Nottingham Trent University have created an artificial eye with a cosmetic pupil that can dilate and contract in response to light. Using smart materials, the prototype aims to solve the longstanding problem of eye-loss victims having two different sized pupils at night or in bright sunshine.
Although artificial eyes today often appear lifelike, none on the open market feature a pupil which can change in size like a real eye. The intention is to increase confidence in people who use prosthetic eyes by making their artificial eye as lifelike as possible.
The research — overseen by Dr Philip Breedon, a reader in smart technologies at the university — was carried out for Nottingham-based firm John Pacey-Lowrie Ocular Prosthetics and took 18 months. Mr Pacey-Lowrie, who has worked in ocular prosthetics for 35 years, said: ‘Many people who have a prosthetic eye are very conscious of how realistic it looks. Young to middle-aged people are especially conscious of being out at night as they are aware that one pupil can often be bigger than the other and it bothers them.’
Now the prototype has been developed successfully, the university will undertake further research to miniaturise it to the size of a human eye.
‘This research is a real breakthrough which promises to end this longstanding problem. The aim is to help people mix in social circles more comfortably and have increased confidence,’ says Pacey-Lowrie.
Made from acrylic resin, the prosthetic eye features a pupil made from carbon paste, and in conjunction with a smart material, it increases in size when an electric current is passed through it.
Powered by a tiny battery, a light sensor in the prosthetic eye communicates with a controller. The controller calculates how much power is needed by the carbon paste to achieve the appropriate size pupil and then sends a charge to the carbon paste along two wires. The artificial pupil then dilates and contracts accordingly.
‘I think that the chances of going to the commercial market with this are strong,’ said Mr Pacey-Lowrie, who trained as an ocularist at Moorfields Eye Hospital in London.
‘It’s not on the market anywhere else in the world. I am very confident that we will be able to miniaturise the technology in the very near future and get it on the open market.’
The second phase of the research, to miniaturise the prototype, has now begun and is expected to run for approximately 18 months.
Dr Breedon, who is based in the university’s School of Architecture, Design and the Built Environment, said: ‘This is a very exciting development which shows how the use of smart materials can potentially improve people’s lives. There is a lot more work to be done, but we are very pleased with some of the initial results as they are very encouraging.
‘It will no doubt be a real challenge to miniaturise the prototype to the smaller size which is needed, but it is something that we believe can be achieved.’
Stephen Shaw, from Derbyshire, UK, suffered a serious eye injury when he was mugged and shot with an air pistol in 1986. Aged 23 years at the time, the projectile from the pistol hit him in the left eye, penetrated his eyelid and caused his retina to detach.
‘I had three operations over a 6-month period to try to repair the damage, but I was rendered blind in my left eye,’ said Stephen.
‘I lived with it for a number of years, but in the late 90s I had cataracts removed and because of the previous treatment I was left with a poorly looking eye. In 1998 I decided to have it removed at the QMC in Nottingham and after that I had a prosthetic eye made.
‘A lot of people don’t realise that I have got an artificial eye. But in low light or bright light it’s noticeable. It’s also very noticeable in photographs because of the flash.
‘Having the prosthetic eye has given me a lot more confidence in day to day life. But to have a pupil that can dilate and contract would be a huge leap forward. It would be a real confidence boost.’