NYSTAGMUS
Jerk Nystagmus
Horizontal Nystagmus
Nystagmus is a condition in which the
eyes make repetitive, uncontrolled
movements, often resulting in reduced
vision. These involuntary eye movements
can occur from side to side, up and down,
Downbeat Nystagmus
Vertical Nystagmus
or in a circular pattern. It may occur in one
or both eyes and as a result, the eyes are
unable to hold steady on objects being
viewed. There are over forty-five different
types of nystagmus. This condition has also been described as dancing eyes or jerking eyes. The
forms of nystagmus include: infantile/congenital and acquired. Early onset begins in infancy and
usually runs in the family. It is observed around the 6th-8th week of life. It is a benign condition
that is not curable. Later in Life acquired nystagmus may occur due to a reaction to certain drugs,
medications, head injury, multiple sclerosis, or brain tumors-some cases it occurs for unknown
reasons. Nystagmus is usually a symptom of some other underlying eye or medical problem. The
exact cause of nystagmus is often unknown. Nystagmus usually does not cause the world to be
constantly moving (occillopsia).
The Affects and Effects on the Visual System
Nystagmus causes the eyes to move involuntarily by “shaking” or “wobbling” thus causing the
eyes to move horizontally (most common) or vertically. Nystagmus causes varying degrees of
vision loss ranging from mild to profound. Early onset nystagmus causes the person’s eyes to
rotate back and forth evenly, much like a pendulum. Late onset nystagmus causes a person to
have vertigo or dizziness related to the new movement they experience in their vision loss.
Nystagmus can accompany astigmatism and retinopathy of prematurely. With the exception of
brief experiences of oscillopsia, most individuals with nystagmus perceive objects as being
stationary. It is believed that the brain is responsible for the perceptual adjustment.
Treatments
Nystagmus cannot be cured but there are several medical and surgical treatments that sometimes
help people with nystagmus. 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. A biofeedback machine acts as a kind of sixth sense, which allows patients
to "see" or "hear" activity inside their bodies, which may help them to control or correct their eye
muscles. Both eyeglasses and contact lenses can help people with nystagmus to see better.
Treatment for other underlying eye or medical problems may help to improve or reduce
nystagmus.
Type of Condition
Nystagmus can be congenital (most common form) when inherited and will appear in early
childhood. It may also be adventitious by developing later in life due to an accident or illness.
Some types of nystagmus improve throughout childhood while others remain stable.
Anticipated Functional Implications
Nystagmus may be helped with prisms and special glasses. The use of large-print books,
magnifying devices and increased lighting can also be helpful. The student may need more time
to take tests due to increase of stress and decrease of vision loss. They may also turn their eyes or
head in a specific manner or need to sit in the front of the classroom. Low vision adaptation may
be required or materials can be enlarged and made with higher contrast. The use of yellow
acetate sheet will help in keeping the student’s place when looking away toward the board or
computer screen. Also the use of a typoscope (card with a rectangular hole, to view one word or
line at a time) or a underliner (card or strip of paper to “underline” the line being read) may be
helpful.
References
American Optometric Association. (n.d.). Nystagmus. Retrieved from
http://www.aoa.org/x9763.xml
Bishop, V. (n.d.). Nystagmus: Selected Anomalies and Diseases of the Eye. Texas School for the
Blind and Visually Impaired. Retrieved from http://www.TSBVI.edu
Dugdale, David. (2011, February 5). Nystagmus . Retrieved from
http://www.nlm.nih.gov/medlineplus/ency/article/003037.htm
Hain, T. (2008, December 10). Nystagmus. Otoneurology Index. Retrieved from
http://www.dizziness-and-balance.com
Vision RX. (n.d.). Nystagmus. Retrieved from http://visionrx.com/library/enc/enc_nystagmus.asp