Nystagmus an involuntary eye movement disorder that affects both eyes. The rapid and repetitive eye movements can be back and forth, up and down, or they can occur in an arc-shaped partially circular direction. Nystagmus typically is accompanied by reduced visual acuity and depth perception, and it can affect balance and coordination. Often, nystagmus is congenital in origin and becomes apparent between 6 weeks and several months of age, and the condition can be inherited. However, nystagmus can affect people of any age, particularly those with neurological disorders.
The prevalence of nystagmus in the general worldwide population is unknown. However, a study in the UK estimated it to be 2.
The study also found that nystagmus was significantly more common among the white European population than in the Asian Indian, Pakistani, other Asian backgrounds populations. 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 when one eye is covered.
Manifest-latent nystagmus is continually present but worsens when one eye is covered. When nystagmus is related to a problem involving the vestibular system in the inner ear or the brain, vertigo, dizziness or loss of balance are almost always present.
Nystagmus usually causes blurry vision in addition to jumping vision. Jerk nystagmus usually results from diseases affecting the inner ear balance mechanisms or the back part of the brain brainstem or cerebellum. Pendular nystagmus can result from brain diseases such as multiple sclerosis , but can be a congenital problem as well. When nystagmus is a new symptom and occurs with new dizziness or vertigo, the patient should get prompt medical attention.
People experiencing pendular nystagmus for the first time should see a neurologist or neuro-ophthalmologist. Although it is not typically an emergency, pendular nystagmus should be assessed promptly. Depending on associated symptoms, the doctor may order tests such as a brain MRI or blood work to rule out a potentially dangerous cause such as stroke.
In other cases, nystagmus may be related to other eye problems. 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. 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. One way to see 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. 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, but having 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 needing to turn 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.
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