When should children have their eyes examined?

It goes without saying that if you have a concern about any aspect of your child’s eye health or vision, then you should book an eye examination irrespective of their age.  Even if a child is too young to identify letters on a chart, there are numerous ways to gather information about you child’s eyes which can be tailored to match their abilities.

Once an image is focused on the back of the eye, the light is converted into electrical signals that pass from the retina, along the optic nerves and to the visual parts of the brain which are situated at the back of the head.

Unlike most other mammals, humans are born with their eyes open which means that all these parts of the visual system begin developing from the moment we are born.  The most rapid development occurs within the first two years of life, however the process continues until at least the seventh birthday.  Constant stimulation of a child’s eyes during this period helps to strengthen the connections between the eyes and the brain and enables them to create an accurate mental picture of the world around them.

Any interruption to the eyes during this developmental period, often called the ‘critical period’ can have long-lasting effects if left untreated.  As such, the earlier that a problem can be identified then the better the outcome for a child’s vision.

The most common reason for parents bringing their children to see me for an eye examination is that they suspect that they may have a squint, which is when the eyes are not perfectly co-ordinated such that one eye may appear to turn in, or less commonly out, too much.  A squint can be present all the time, or just on occasions, such as when tired, when reading or looking far into the distance.  If a child has a squint, then there is a chance they may develop a ‘lazy eye’ which is when the brain switches off the images received from the eye that squints, in order to avoid confusion.  As a consequence, the parts of the visual area of brain that respond to images from that eye fail to develop properly.  Lazy eye can also happen without a squint, particularly if there is a difference in the shape or size of the eyes which have caused to long sight or astigmatism.

The good news is that most squints and lazy eyes respond well to correction with glasses, and if either of these aspects persists, then there are orthoptists (hospital-based children’s vision specialists) who can give further treatment in the form of patching or exercises.

Squints and lazy eyes are relatively common and are thought to affect as many as one person out of every 25, although they certainly tend to run in families.  It is important, therefore, to ensure your children have an early assessment of their eyes if a parent or sibling has been affected in order that it can be detected as early as possible. 

Remember, all children under 16 are entitled to an NHS sight test which is free-of-charge.

In the next article, we will look at other good reasons to bring children to have their eyes tested