Nystagmus is a condition where the eyes move rapidly and uncontrollably. They can move:
- side to side (horizontal nystagmus)
- up and down (vertical nystagmus)
- in a circle (rotary nystagmus)
The movement can vary between slow and fast and usually happens in both eyes. The eyes may shake more when looking in certain directions. People with nystagmus may tilt or turn their head to see more clearly. This helps to slow down the eye movements.
Nystagmus in children and adults
There are two types of nystagmus: congenital and acquired.
Congenital nystagmus
This type of nystagmus starts in infants, usually between 6 weeks and 3 months old. Children with this condition tend to have it in both eyes, which move side to side. Usually doctors do not know the cause of the nystagmus in children, although it may be inherited (passed down from parents to child).
Children with nystagmus typically do not see things as “shaking.” Instead, they may have some blurry vision.
Acquired nystagmus
This condition happens later in life. It has many causes, including serious medical conditions or drug and alcohol use.
Unlike children with congenital nystagmus, adults with nystagmus often say that things around them look shaky.
Nystagmus Causes
The brain controls eye movement. Your eyes move automatically to adjust when you move your head slightly. This stabilizes the image that you are looking at so you see a sharper image. In people with nystagmus, the areas of the brain that control eye movements do not work properly.
In some cases, it is not clear why someone has nystagmus. In other cases, nystagmus may be related to other eye problems.
Nystagmus can be related to the following:
- Having a family history of nystagmus
- Albinism (lack of color, or pigmentation, in the skin)
- A wide range of eye problems in infants and children, including cataracts, strabismus and focusing problems
- Inner ear problems, such as Meniere’s disease
- Multiple sclerosis
- Stroke (a common cause of acquired nystagmus in older people)
- Head injury (a common cause of acquired nystagmus in younger people)
- Use of certain medications, such as lithium or anti-seizure medications
- Alcohol or drug use
Nystagmus Symptoms
The main symptom of nystagmus is rapid eye movement that cannot be controlled. Usually the movement is side to side. It can also be up and down or circular. The movement can vary between slow and fast, and it usually happens in both eyes.
In addition to rapid eye movement, nystagmus symptoms include:
Nystagmus Diagnosis
Nystagmus is diagnosed by an ophthalmologist. They will examine the inside of your eyes and test your vision. Your ophthalmologist will also look for other eye problems that may be related to nystagmus. These can include strabismus (misaligned eyes), cataracts (clouding of the eye’s lens), or a problem with the eye's retina or optic nerve.
One way to test for nystagmus is to spin a person around for about 30 seconds, stop and then have them try to stare at an object. If they have nystagmus, their eyes will first move slowly in one direction, then move rapidly in the opposite direction.
Other tests that may be used to diagnose nystagmus are:
- eye-movement recordings (to confirm the type of nystagmus and see details of the eye movements)
- an ear exam
- a neurological exam
- tests to get images of the brain, including computerized tomography (CT) and magnetic resonance imaging (MRI)
Nystagmus Treatment
Treating nystagmus depends on the cause. People born with nystagmus cannot be cured of this condition. However, they may benefit from glasses or contact lenses. These do not fix the nystagmus; however, clearer vision can help slow the eye movements.
Rarely, surgery may be done to reposition eye muscles that move the eyes. This keeps the head from turning as far to keep the eyes from moving. However, surgery does not correct or cure nystagmus. It just allows someone to keep their head in a more comfortable position to limit eye movement.
Sometimes, acquired nystagmus can go away. This happens if the condition that causes the nystagmus is treated. That can include treating a medical problem or stopping drug or alcohol use.