The camera that spots a squint before it’s too late

PAUL MORLAND’s sight is good enough for driving but fiddly tasks are all but impossible and if he had wanted a career that required good vision, such as being a pilot or surgeon, he would have been automatically ruled out — because he is effectively blind in one eye.

This could have been prevented if Paul’s problem had been spotted sooner. Like at least a million people in the UK, Paul, 50, has a squint (when the eyeballs do not follow each other because the muscles around them do not work in synchronicity).

A squint may be obvious, causing the affected eye to turn inwards, outwards, upwards or downwards, when the other eye is looking straight ahead (giving the impression of being ‘cross- eyed’). However, the squint may not occur all the time, and a minor squint may not always be obvious because there is no correlation between the degree of squint and its effect on vision.

If left untreated, the affected eye is not used for focusing and eventually becomes ‘lazy’, causing blurred vision.

Lazy eye is caused when the part of the brain associated with vision, the visual cortex, ignores messages coming from that eye. Lazy eye can also lead to a lack of 3d vision (which requires input from both eyes), making it difficult to judge how fast objects such as a football are moving.

squint, whose clinical name is strabismus, affects around one in 20 children in Britain and without treatment most of those will develop a lazy eye (amblyopia), the major cause of one-eyed blindness in the under 40s. People under 20 are ten times more likely to lose their vision due to lazy eye than through trauma and disease combined.

Treatment usually takes the form of eye patches that encourage the muscles in the lazy eye to work or, in the worst cases, surgery, which involves adjusting the muscles in the turned eye to enable both to work together. The Countess of Wessex recently spoke of how her daughter, Lady Louise Windsor, 11, developed a ‘profound squint’ as a result of her premature birth, which was resolved with the help of surgery. OFTEN the condition does not get picked up until it is too late for treatment to be effective. As dr simon Barnard, a Londonbased optometrist, says, visual development moves on rapidly between the ages of one and five, and treatment after this age has little chance of success.

‘It’s a bit like cement drying — the quicker you start work, the more time you will have before it sets,’ he says. ‘After the age of eight the chances of success are much lower.’

Yet screening of young children is not uniform in this country, partly due to a shortfall in the number of specialist orthoptists trained to pick up such problems in children.

Paul’s squint was not spotted until he was five. However, when he was one his mother had concerns about his eyes and took him to have them checked.

‘squints run in my family, so my mother took me to a specialist. The specialist examined me, but told her there was nothing wrong,’ says Paul, a business consultant and a political scientist who lives in north London with his wife and their three children aged 21, 19 and 16.

When he was five, his mother decided to get a second opinion and he was diagnosed with a squint in his right eye — which had by then become ‘lazy’.

He was made to wear a plaster over his good eye to try to encourage the lazy one to work, but after two years there was no improvement and Paul was told that his squint had been picked up too late to be helped.

‘I even tried some further treatment in my teens, which took the form of special exercises and trying to read with my good eye covered, but they made no impact to speak of,’ he says.

‘The effect on my sight has been huge: I have a very narrow field of vision and poor 3d vision, which means that I find it hard to judge fast-moving objects and simple tasks like threading a needle are almost impossible.

‘As a child, ball sports were ruled out and while my peers enjoyed tennis and rugby, I had to concentrate on running.

‘ Having to wear patches at primary school also made me feel awkward.

‘I had to be cautious in the playground, as I needed to take especially good care of my good eye. ‘I am just lucky that I have very good vision in that eye and so I have been able to rely on that and can even drive. ‘nevertheless, if my squint had been treated earlier it would have made my daily life easier and more opportunities would have been open to me.’ In Britain, babies are currently checked for squints at birth and during the six to eightweek check, usually by a health visitor who will look for symmetry by shining a light in the baby’s eye. At that point, if a concern is raised the child will be referred to a specialist.

Most squints are picked up during screening in the first year of school, where tests such as a vision chart are used to assess quality of sight. However, by this time the chance of any necessary treatments being successful is reduced. furthermore, children’s sight testing in the UK may not be offered in some areas, says Geoff roberson, of the Association of optometrists (AoP).

He says: ‘even where screening is provided in schools there are many conditions which, although they may cause significant problems to a child and to their ability to learn, will not be picked up.’

After the first year of school, there is no screening as such. Children can have free sight tests up to the age of 16 (or to under 19 if they are in full-time education), but the onus is on the parents to take their child to an optometrist. YET, according to the AoP, more than 90 per cent of children visit a dentist regularly while only 53 per cent have ever had an eye examination.

A further problem is t hat parents tend to assume that eye problems will be obvious, but small children often become so accustomed to their level of vision that, even if impaired, it may not be apparent.

Around 20 per cent of schoolaged children i n the UK currently have an undiagnosed sight problem, according to the AoP, which is campaigning to raise awareness of the importance of children’s eye tests.

‘Health visitors do their best, but it is very hard to pick up less obvious squints,’ says dr Barnard, who has recently developed a piece of equipment which he hopes will make this crucial early detection easier and more accurate.

The Volk eye Check is a handheld camera that can identify a squint with a single flash photograph. It has a patented childfriendly ‘target’ with coloured lights on the front to draw the child’s focus to the correct area so an accurate image can be captured.

The camera software then looks at 17 data points to measure the alignment of the eye.

Any lack of symmetry means that the child’s vision should be investigated further. The whole process takes place around two minutes and the test can be used from four months on.

research by the developers on 331 cases found an 84 per cent success rate in diagnosing squints in babies and young children.

furthermore, an independent study recently completed by the Michigan College of optometry in the U.s. has confirmed the accuracy of the measurements taken in dr Barnard’s test.

The hope is that it could make low-cost squint screening widely available, possibly carried out by a health visitor. However, it has yet to be picked up by the nHs, although the device is already being used in some High street opticians.

The importance of identifying squints and other eye problems in young children cannot be underestimated, says Geoff roberson.

‘Undiagnosed eye problems can contribute to poor performance and poor behaviour in t he classroom.

‘early treatment may also allow better career opportunities, particularly in fields with specific vision requirements.’