Vision Information - Nystagmus
Nystagmus is a vision disorder in which the eyes make repetitive, uncontrolled movements that often result in reduced vision. The movements can occur from side to side, up and down, or in a circular pattern. The problem emanating from the condition is that both eyes are unable to hold steady on objects viewed. Sometimes nystagmus patients can be observed nodding their heads or holding them in unusual positions to compensate.
Nystagmus is recognized in three forms:
Congenital - mostly develops by 2 to 3 months of age. The eyes tend to move in a horizontal, swinging fashion and the disorder is often associated with other conditions such as congenital cataract, congenital absence of the iris, albinism, and underdeveloped optic nerves.
Spasmus nutans - usually occurs between ages 6 months and 3 years but resolves spontaneously between 2 and 8 years of age. Children with this form often display head nodding and a head tilt and their eyes can move in any direction. This form of nystagmus usually does not require treatment.
Acquired - This form of nystagmus develops later in childhood or in adulthood. The cause is mostly unknown but it is widely thought to be due to central nervous system and metabolic disorders or alcohol and drug toxicity.
Another classification of nystagmus is by the type of motion the eyes make:
Pendular nystagmus - diagnosed as such when the speed of movement of the eyes is the same in both directions.
Jerk nystagmus - diagnosed as such when the eyes move slowly in one direction and quickly â€œjerkâ€ back in the other direction.
What Causes Nystagmus?
Nystagmus is the direct result of the instability or impairment of the system responsible for controlling eye movements. When it develops in early childhood it may be the result of a problem in the visual pathway from the eye to the brain. Usually, the child has no other eye or medical problem. Acquired nystagmus, which occurs later in life, can be a symptom for another condition like stroke, multiple sclerosis or a blow to the head.
Nystagmus can also be caused by the following:
Treatment of Nystagmus
Nystagmus is not a curable disorder. While eyeglasses and contact lenses do not correct nystagmus, they can help to correct other vision problems associated with the disorder such as short-sightedness, far-sightedness or astigmatism.
Some forms of nystagmus will improve throughout childhood and vision can be enhanced with the use of prisms and special glasses. Large-print books, magnifying devices and increased lighting can also be helpful.
Surgery is sometimes - though rarely - performed to alter the position of the muscles which move the eyes. While it won't cure the condition, it can reduce the amount of head turn needed for best vision.
Treatment of other underlying eye or medical problems may help to improve or reduce nystagmus.
A comprehensive eye examination by your ophthalmologist should detect the presence or otherwise of nystagmus. But since the condition is often the result of other underlying health problems, your ophthalmologist may refer you to your primary care physician or another medical specialist for further testing.