Nystagmus

Back and forth eye movements; Involuntary eye movements; Rapid eye movements from side to side; Uncontrolled eye movements; Eye movements - uncontrollable

Nystagmus is a term to describe fast, uncontrollable movements of the eyes that may be:

  • Side to side (horizontal nystagmus)
  • Up and down (vertical nystagmus)
  • Rotary (rotary or torsional nystagmus)

Depending on the cause, these movements may be in both eyes or in just one eye. The term "dancing eyes" has been used to describe nystagmus.

External and internal eye anatomy

The cornea allows light to enter the eye. As light passes through the eye the iris changes shape by expanding and letting more light through or constricting and letting less light through to change pupil size. The lens then changes shape to allow the accurate focusing of light on the retina. Light excites photoreceptors that eventually, through a chemical process, transmit nerve signals through the optic nerve to the brain. The brain processes these nerve impulses into sight.

Considerations

Causes

Home Care

When to Contact a Medical Professional

What to Expect at Your Office Visit