My name's Michael Clarke, I'm a consultant paediatric ophthalmologist

a children's eye doctor, at the Newcastle Hospitals Trust.

Having normal vision is essential to children's normal development.

So there are a number of stages at which

children's vision and their eyes are assessed.

Assessing the eyes as structurally normal is part of a normal exam

around the time of birth.

And then eyes are checked again usually at the six-week check

and then the next main test is at four,

and the main purpose of that test is to detect poor vision in one or both eyes.

That's important because the child is about to enter school

or will have just entered school

and having normal eyesight is very important to a child's education

as well as to the rest of its life and development.

The person doing the tests, who is often an orthoptist,

a paramedical professional specially trained in assessing children's vision,

will show the child a card with some pictures or letters on it,

depending on the state of the child's development and attention,

and will ask the child to identify the letters or symbols on the card.

The most common problem that arises to do with children's eyesight

is a condition called amblyopia or lazy eye,

and that means that the brain, that deals with vision,

hasn't developed the normal connections that should occur during development.

A child's vision isn't fully developed at birth

and for the bit of the brain that deals with vision to develop properly,

it requires a normal image from the eye to be fed back to the brain

so that the right connections are made.

That can be affected by things like refractive error

which is the need for glasses

or by the development of a squint in which one eye turns in

or by other more serious problems which can occur in children,

like cataracts or glaucoma.

A screening test is recommended for children around the age of four

because often children with poor vision in one eye won't make any complaints,

they just learn to adapt to it and use their other eye,

so that's why it's important the vision is checked in each eye individually.

If a parent, around that time or before then,

notices that their child isn't seeing properly or develops a squint,

they should seek medical attention.

But quite often the child won't make any complaint about poor or double vision,

they'll just assume that's normal for them and adapt to it.

Beyond the age of four or five,

the impact of having blurred vision on the normal development of the brain

becomes much less important and children and young people older than that

are more able to describe problems they're having with their vision.

Beyond those ages,

there isn't usually a medical problem to account for poor vision,

it's usually a refractive problem to do with the optics of the eyes

that can be cured by glasses.

So if anybody has a problem with reduced vision beyond the age of four or five,

we recommend they go to their local optometrist for a routine eye check

and get glasses if they're helpful.