Nystagmus. Perhaps this is a word you have not heard of before. Despite its relative obscurity, this condition has a profound effect on the eyes, and tends to manifest during childhood. Expert ophthalmologist Mr Richard Bowman explains:
What is nystagmus?
Also known as “dancing eyes”, nystagmus is a relatively common eye condition in which the eyes are almost constantly moving – usually in rapid, uncontrolled motions. The movements vary depending on the individual case and the type of nystagmus. The eyes may move from side to side, up and down, or in a circular motion. The constant movement makes it difficult for the individual to focus on a particular spot, which can reduce vision and depth perception.
What are the symptoms of nystagmus?
Nystagmus symptoms mainly involve uncontrolled movements of the eyes. Nystagmus usually affects both eyes; it is very rare for it to only affect one. These usually rapid movements make it difficult for the patient to look at an object steadily, impairing vision. In some cases, the reduction in vision caused by nystagmus can be enough for a person to be declared legally sight impaired, especially if paired with another eye condition. The inability to focus can also have an impact on balance and coordination, in more serious cases leading to vertigo and nausea.
People with nystagmus may find that tilting or holding their head in a certain position may make it easier to focus. This is known as the “null point” – a position in which the eyes move the least.
There are different types of nystagmus:
- Infantile, or congenital nystagmus – present from birth, the child’s eyes oscillate like a pendulum, swinging from side to side. It may be associated with conditions like albinism or congenital cataracts.
- Manifest latent nystagmus (fusional maldevelopment nystagmus) – associated with early loss of binocular vision, most commonly in the presence of a squint. This type of nystagmus may not be seen all the time.
- Acquired nystagmus – Usually occurs in later childhood or adulthood. While it has been linked to various other conditions or events, such as metabolic and nervous system disorders, drug and alcohol abuse, and trauma, the cause is often unknown.
What causes nystagmus?
- Loss of vision early in life e.g. congenital cataracts, or retinal dystrophies
- Genetics – some forms of infantile nystagmus, albinism
- Central nervous system conditions such as stroke, multiple sclerosis, or brain injury around the time of birth
- Inner ear conditions, e.g. Meniere’s disease
Living with nystagmus
Shaking eyes caused by nystagmus tends to be more pronounced in children than in adults, and indeed, in some patients the condition disappears as they mature. However, most have the condition for life. Glasses and contact lenses can help to improve vision, and there may be surgical and medical options to reduce the severity of the “dancing eyes”.
If you or your child are showing signs of nystagmus, you shouldn’t worry too much – people with this condition can usually live normal lives, with relatively normal vision, as long as the condition is properly managed. You should consult an ophthalmologist to find out the cause of the nystagmus and the best course of action for you.