Duane syndrome

What is Duane syndrome?

Duane syndrome, also known as Duane retraction syndrome, is an eye movement disorder that you are born with. There are several types - in the most common type, one eye cannot move outward fully. The other types affect inward or both inward and outward movement in one eye.

What causes Duane syndrome?

Duane syndrome is caused when one of the nerves that controls how the eye moves outwards (the sixth nerve) doesn't form properly, so it doesn't properly control the eye muscles. The connections of another nerve (the third nerve) can also be affected, causing trouble with inward movement.

In rare cases, Duane syndrome is inherited. If so, it’s due to a faulty gene called CHN1.

What are the signs and symptoms of Duane syndrome?

People with Duane syndrome find it very hard to move the affected eye outwards towards the ear. When they try, the eyelid opening gets wider. It may also be hard to move the eye inward towards the nose. Most people with Duane syndrome have eyes that look in different directions (a strabismus), but only when looking to one side. If so, they can compensate with a subconscious turn of the head and avoid it.

About 3 in 10 people with Duane syndrome have other conditions too, such as being born deaf or having problems with their backbone (spine).

How is Duane syndrome diagnosed?

Diagnosis of Duane syndrome typically involves a clinical examination by an eye specialist, who will evaluate the eye movements and look for characteristic signs such as limited outward or inward movement and changes in eyelid position. Family history and genetic testing may also be used to support the diagnosis, especially in cases with a known genetic component.

Is Duane syndrome serious?

Duane syndrome is not progressive, so it doesn’t get better or worse over time. While it can cause difficulties with eye movement and positioning, most people with Duane syndrome can compensate with a head turn.

What are the treatments for Duane syndrome?

Most people with Duane syndrome don't need treatment because they can compensate by turning their head. If it's not possible to compensate with a head turn, or if the head turn that works means people have to hold their head in a difficult position, then surgery may be needed.

The missing nerve cannot be replaced, so the aim of surgery is to move the affected eye to a more central position. This makes it easier to use a smaller head turn to get the eyes to fix on the same spot at the same time. Surgery cannot make eye movement easier.

What research is there into Duane syndrome?

Fight for Sight researchers helped to identify one of the genes (CHN1) that is faulty in Duane syndrome, and research is centred on studying the way that nerve cells grow during development. The aim is to understand enough to begin developing a treatment.