Nystagmus: Involuntary eye movements
Nystagmus is the term used to describe involuntary repetitive eye movements that make it impossible for a person to keep their eyes fixed on any given object.
There are two basic types of nystagmus:
- Jerk nystagmus — the eyes make a very quick movement in one direction, followed by a slower movement in the opposite direction.
- Pendular nystagmus — the eye movements are of equal velocity in each direction.
Nystagmus is usually infantile, meaning people have it from a very early age. Experts say that about one child out of every several thousand has nystagmus.
Different kinds of nystagmus include:
- Congenital nystagmus
- Manifest nystagmus
- Latent nystagmus
- Manifest-latent nystagmus
- Acquired nystagmus
Congenital nystagmus is present at birth. With this condition, your eyes move together as they oscillate (swing like a pendulum). Most other types of infantile nystagmus are also classified as forms of strabismus, which means the eyes don't necessarily work together at all times.
Manifest nystagmus is present at all times, whereas latent nystagmus occurs only when one eye is covered.
Manifest-latent nystagmus is continually present, but worsens when one eye is covered.
Acquired nystagmus can be caused by a disease (multiple sclerosis, brain tumor, diabetic neuropathy), an accident (head injury), or a neurological problem (side effect of a medication, for example).
Hyperventilation, a flashing light in front of one eye, nicotine and even vibrations have been known to cause nystagmus in rare cases.
Some types of acquired nystagmus can be treated with medications or surgeries.
Nystagmus causes, symptoms and challenges
As mentioned above, most people with nystagmus are born with the condition or develop it early in life. Unless induced by trauma or disease, nystagmus almost always is caused by neurological problems.
Two other classifications of nystagmus are:
- Optokinetic (eye related)
- Vestibular (inner ear related)
People with inner ear problems can develop jerk nystagmus. Because of the motion of the eyes, people with this condition can develop nausea and vertigo. This type of nystagmus, usually temporary, also can occur in people with Meniere's disease (an inner ear disorder) or when water settles into one ear. Taking a decongestant sometimes can clear up this type of acquired nystagmus.
All forms of nystagmus are involuntary, meaning people with the condition cannot control their eyes. Sometimes, infantile nystagmus improves slightly as a person reaches adulthood; however, it also can worsen with tiredness and stress.
Having nystagmus affects both vision and self-concept. Most people with nystagmus have some sort of vision limitations because the eyes continually sweep over what they are viewing, making it impossible to obtain a clear image.
Some people with nystagmus have so many vision problems that they can be considered legally blind.
If you have nystagmus, not only is your appearance affected, but you literally see in a way that is different from people who don't have the condition. Your eyes are in constant motion.
To see better, you may need to turn your head and lock your eyes into what's called the "null point." This is a certain head angle that makes the eyes move the least, stabilizing the image for better vision.
When you have nystagmus, you must deal with the personal and social consequences of this difference.
Nystagmus can affect nearly every aspect of your life, including how you relate to other people, your educational and work opportunities and your self-image.
Counseling may be helpful as you face the social and personal challenges often associated with nystagmus.
Can nystagmus be treated?
Several medical and surgical treatments that sometimes help people with nystagmus are available. Surgery usually reduces the null positions, lessening head tilt and improving cosmetic appearance.
Drugs such as Botox or Baclofen can reduce some nystagmic movements, although results are usually temporary.
Some people with nystagmus benefit from biofeedback training.
If you have nystagmus, make sure you undergo regular eye exams so you can be monitored for both health and vision issues.
Both eyeglasses and contact lenses can help people with nystagmus see better, but I have found contact lenses to be the superior alternative for many with nystagmus. With glasses, the eyes sweep back and forth over the lens centers and vision is not as clear. With contacts, however, the lens centers move with the eyes.
Helping children with nystagmus
Usually, nystagmus is discovered at a very young age. Parents and caretakers, here's how you can help a child who has nystagmus:
- Find an eye doctor you trust who understands and treats nystagmus.
- Make sure your child's glasses or contact lenses are always up-to-date and that vision is corrected to the maximum level possible.
- Help your child's teachers understand the basics of nystagmus, including how the condition affects ability to see, learn and interact with other children.
- Develop a comfort level with explaining nystagmus to family, friends and others who notice your child's eyes swinging back and forth. Keep your explanation short, to-the-point and positive.
- Don't lower your expectations for your child. Most people with nystagmus can see, learn and interact well enough to lead very normal lives.
- Be positive. Nystagmus, while a visible "disability," is not the end of the world. As they grow up, children with nystagmus need help in understanding why their eyes are different. Reassure children that nystagmus won't stop them from being normal kids and normal adults. — Dr. Dubow
Page updated April 2019