Congenital nystagmus

Congenital nystagmus simply means nystagmus that is noticed in very young children. This is usually seen soon after they are born or sometimes in the first couple of years of their life. This type of nystagmus can be caused by either a problem with the eye itself or by a problem with the visual pathway from the eye to the brain.

Although both doctors and researchers are still uncertain about what causes nystagmus, in the overwhelming number of cases it is connected to impaired vision.

## How is congenital nystagmus diagnosed?

Many cases of nystagmus are picked up at between six weeks and three months in a baby’s development as this is the stage at which babies’ eyes start to seek focus. Developmental checks by a health visitor or at the local medical clinic may not pick the condition up, as it is notoriously difficult to diagnose eye conditions in young babies.

Therefore, often the parent, or someone else in the family, is the first to notice that something is wrong as the baby’s eyes may fail to ‘fix’ on a toy or other object. This means that the baby cannot follow with his/her eyes an object moved slowly across their field of vision and, if his/her name is called, cannot readily find the source of the voice across a room. If this is noticed the child should be taken to see their GP who may then refer them to an eye specialist (an ophthalmologist).

## How is congenital nystagmus treated?

As nystagmus is a symptom, doctors use a range of tests, such as VEPs (Visual Evoked Potentials, sometimes known as VERs or Visual Evoked Responses) and ERG (electro-retinogram) to try to identify the underlying cause. These are both painless ways of checking activity in the brain to try to establish what the underlying condition is.

It is very common for doctors to say that an individual’s nystagmus is idiopathic – this means no cause known. Getting a diagnosis is important because there could be a genetic basis to the condition that can have implications for an individual’s family. However, in terms of treatment there is very little available other than improving the child’s other sight issues by wearing glasses and/or contact lenses.

## How does congenital nystagmus affect vision?

In congenital nystgamus the “wobble” of the eye is not directly related to how well or badly a child can see. Some children whose nystagmus is barely visible may still have quite impaired vision while others whose nystagmus is much more obvious may be at the better end of the spectrum. However, an individual with congenital nystgamus has sight that is generally stable and it is not generally a deteriorating condition.

Most people with nystagmus read relatively comfortably and although they have few problems with mobility new technology (such as smart phones and tables) has had a huge impact as these devices and their apps have made getting around a lot easier. However, most people with nystagmus do not drive and this is possibly the single biggest frustration for most people with this condition. In addition, many parents find that one of the most obvious impacts of their child’s nystagmus is to make them extremely short-sighted in a non-correctable way.

## Can congenital nystagmus be cured?

Unfortunately there is currently no cure for nystagmus. The cause of many children’s nystagmus is different as it stems from something being wrong in either the retina, visual pathways, or both and in many cases the cause is still unknown.

In recent years there has been a lot of work in developing the knowledge about the underlying problems with the visual system that lead to nystagmus and correcting problems in the eye without risking what good sight there is presents doctors with an immense problem. Researchers are currently looking at using drugs to reduce nystagmus and therefore improve vision, although this work is at early stage trials and not suitable for the participation of children.