- Breakthrough could restore sight to millions
- Groundbreaking implant good enough to recognise faces
Scientists have made blind mice see clearly again in a breakthrough that offers hope to millions.
The creatures’ vision was good enough to distinguish a baby’s face, see many of the details of a scene in a park and track a moving image.
The technique, using high-tech spectacles containing a tiny camera rather than surgery, could be tested on people for the first time in just one to two years
Scientists have made blind mice see clearly again. The creatures¿ vision was good enough to distinguish a baby¿s face.
Sheila Nirenberg, the neuroscientist who is honing the technique, says the ultimate hope is the blind will be able to ‘see patterned images, see faces, walk through the supermarket and pick out a box of cereal, recognise their children’.
‘This has all been thrilling,’ she said.
‘I can’t wait to get started on bringing this approach to patients.’
The researchers hope the bionic eye will lead to spectacles that could replace a healthy retina (top example) with an artificial electronic encoder one (bottom)
The first beneficiaries are likely to be sufferers of age-related macular degeneration, the most common cause of blindness in the elderly.
It affects some 500,000 Britons and the figure is expected to treble in the next 25 years as the population ages.
A shows normal vision. B and C shows the image the blind mice saw after the new treatment. D shows the image they would see using the current, not as good, treatment
But there are few treatments and no cure for the condition which makes it difficult or impossible to carry out everyday tasks such as reading, driving and watching television.
Scientists have already created implantable chips that restore some vision.
But Dr Nirenberg says that her technique produces a much clearer picture. In fact, vision is close to normal.
When we look at something, light falls on cells in the retina, the ‘film’ at the back of the eye and is converted into electrical signals which are sent to the brain for processing into images.
The electrical signals are encoded, with the pattern for a dog, for instance, being different to that for a cat or a baby.
In age-related macular degeneration, the retinal cells that pick up light die off, leading to less information being passed to the brain and vision deteriorating.
Dr Nirenberg has found a way of bypassing these cells and sending the encoded information directly to the brain.
Crucially, she has also worked out how to accurately encode the information.
This results in much clearer images that existing devices that simply concentrate on gathering the light and sending the data to the brain.
Researchers hope the latest breakthrough could lead to radical new treatments for humans and restore sight to millions
Experiments on mice show the technique to produce near normal vision, the journal Proceedings of the National Academy of Sciences reports.
Dr Nirenberg, of Weill Cornell Medical College in New York, has now worked out the coding for monkey’s eyes.
With the human eye relying on the same code, the first human trials could be just one to two years away.
If the technique is shown to be safe and effective, it could be in widespread use five to seven years after that.
Dr Nirenberg, who needs more funding to complete her research, envisages the blind wearing chunky spectacles, or even a Star Trek-like visor, embedded with a tiny camera.
This will pick up the information in the person’s line of vision and, using a mobile phone-sized processor, turn it into the code used by the eye.
The code will then be turned into flashes of light by a mini projector, also hidden in the glasses.
These flashes of light will in turn activate cells at the back of the retina, which will pass the information encoded in the pulses of light to the brain.
To add to the complexity, a jab of genes will be needed to make the cells that pass on the data sensitive to the flashes of light.
Dr Nirenberg said: ‘This is the first prosthetic that has the potential to provide normal or near-normal vision because it incorporates the code.
‘It is an exciting time.
‘We can make blind mouse retinas see and we’re moving as fast as we can to do the same in humans.’
Clara Eaglen, of the Royal National Institute of Blind People, said: ‘This is very interesting research – particularly as age-related macular degeneration is the leading cause of sight loss in the UK and research indicates that there will be an increase in the number of people diagnosed over the next decade.
‘Clearly it is still at an early stage and more extensive trials are needed to confirm the safety and effectiveness of this kind of treatment, but at some point in the future prosthetic retina implants may become part of the armoury of treatments for sight-threatening eye conditions.’