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Eye movements - uncontrollable

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Eye movements - uncontrollable

Definition:

Uncontrollable eye movements are involuntary, rapid, and repetitive movement of the eyes.

Alternative Names:
Back and forth eye movements; Involuntary eye movements; Nystagmus; Rapid eye movements from side to side; Uncontrolled eye movements

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Considerations:

Nystagmus refers to rapid involuntary movements of the eyes that may be from side to side (horizontal nystagmus), up and down (vertical nystagmus) or rotary. Depending on the cause, these movements may be in both eyes or in just one eye. The term "dancing eyes" has been used in regional dialect to describe nystagmus.

The involuntary eye movements of nystagmus are caused by abnormal function in the areas of the brain that control eye movements. The exact nature of these disorders is poorly understood. Nystagmus may be either congenital (present at birth) or may be acquired (caused by disease or injury later in life).

CONGENITAL NYSTAGMUS

Congenital nystagmus is more common than acquired nystagmus. It is usually mild, does not change in severity, and is not associated with any other disorder.

Affected people are not aware of the eye movements, although they may be noticed by a careful observer. If the movements are of large magnitude, visual acuity (sharpness of vision) may be less than 20/20. Surgery may improve visual acuity.

Rarely, nystagmus occurs as a result of congenital diseases of the eye that cause poor vision. Although this is rare, an ophthalmologist should evaluate any child with nystagmus to check for this.

ACQUIRED NYSTAGMUS

A less-common cause of nystagmus is disease or injury of the central nervous system.

In young people the most common cause of acquired nystagmus is head injury from motor vehicle accidents. In older people the most common cause is stroke (blood vessel blockage in the brain). Any disease of the brain (such as multiple sclerosis or brain tumors) can cause nystagmus if the areas controlling eye movements are damaged.