Nystagmus is the term that describes the uncontrollable shaking of the eyes. It can occur in healthy eyes as well as in the eyes of children born with congenital eye pathologies such as albinism, cataracts, glaucoma, Aniridia, optic nerve hypoplasia, and retinopathy of prematurity. Patients with nystagmus may have 20/20 sight or sight as poor as 20/400. It is sometimes an inherited trait that affects males and females equally. In many cases, nystagmus will improve with age, but it is rare that this condition is eliminated with treatment.
Nystagmus is described on the basis of the direction of the eye movements. Horizontal nystagmus is the most common form of nystagmus where the eyes move uncontrollably in a horizontal manner. Horizontal nystagmus often consists of a rapid phase where the eyes move quickly towards one direction and slowly in the other direction. Consequently, horizontal nystagmus is also called jerk nystagmus because the eyes pull quickly in one direction. Pendular nystagmus describes the condition where the eyes move back and forth similar to a pendulum of a grandfather clock.
Vertical nystagmus describes nystagmus where the eyes move up and down vertically. In all forms of nystagmus, the speed and degree of nystagmus correlates with the level of vision. Patients with rapid nystagmus tend to have better vision as compared to those with slow moving nystagmus. Similarly, patients who have a small degree of movement tend to have better sight than those with significant levels of movement.
However, no matter the type of nystagmus, the quality of life of the patient in question can suffer to the problems associated with this condition. That is why it is essential to try everything that can soothe the symptoms and facilitate the various issues that appear after suffering a nystagmus attack. We all want to have a healthy vision, and nystagmus is a condition that can strike all of us. Therefore, it is important to learn about the problem and to try and come up with satisfying and efficient solutions. In the end, clients who are suffering from nystagmus will reap the benefits of those efforts, and their overall quality of life will significantly improve.
Patients with nystagmus frequently turn or tilt their head to position their eyes to minimize the nystagmus. For many patients, nystagmus will reduce when the eyes are placed in a particular field of gaze. This place is called the null point. The null point tends to differ for each person. The use of prismatic spectacles and eye muscle surgery are sometimes used to position the eyes in the null point to reduce or eliminate the head turn or tilt that sometimes co-exists with nystagmus.
Patients with congenital nystagmus do not perceive the world as moving or shaking. However, adults who acquire nystagmus secondary to stroke, cerebral vascular accidents or trauma typically are bothered by the shaking or movement of the images that they see. Consequently, many adults with acquired nystagmus keep their eyes closed and don’t use their vision as an attempt to minimize the dizziness and nausea they experience due to the moving images.
Unfortunately, no treatment completely eliminates or cures nystagmus. Nystagmus that is present among young infants often improves with time. The use of corrective glasses, vision therapy, rigid contact lenses, and eye muscle surgery can reduce nystagmus. There are some cases of nystagmus in which the nystagmus is only present when one eye is covered. This condition is called latent nystagmus and can be prevented by not winking, closing, or covering one eye. For these children, it is important to keep their hair away from their eyes and to position them such that they have an unobstructed view of the chalkboard with both eyes. Nystagmus can increase among patients when they are tired, nervous, or when they look towards their extreme right and left fields of gaze.
Infants with nystagmus must be evaluated by a pediatric ophthalmologist to rule out potential neurological problems.
An eye examination by a developmental optometrist can provide spectacles, prisms, and vision therapy activities to attempt to reduce nystagmus.
Patients with blurred sight due to nystagmus will benefit from a consultation by a low vision specialist and low vision aids. Bioptic spectacles, specialized reading glasses, wide-angle magnifiers, and closed circuit televisions can be very helpful.
Students should be provided with additional time for reading, writing, and copying from the chalkboard. Nystagmus can interfere with the efficiency of moving the eyes in a “left to the right” reading pattern.
Students with vertical or Pendular nystagmus will benefit from using wide-bold lined paper to help them to maintain their place when writing.
Thick pencils, bold markers, and 1.0 mm gel pens are easier for students to read their writing if they have nystagmus and blurred sight.
Students with blurred sight will benefit from having access to handouts and other materials that are typically presented on the board.
The use of bold architecture chalk and bold dry erase markers with black ink will help students with nystagmus and blurred sight to access written material on the board.
The use of large print textbooks can be very helpful to assist students who have difficulty tracking letters and words when reading.
Modifications to the computer screen to enlarge the font size and spacing are very helpful. For instructions, please see Solutions to Help You Use the Computer.
Specialized software programs are available that will modify the size of the fonts and spacing between letters to make reading easier for students with moderate to severe nystagmus. For more details, see Computer and Assistive Technology.
The following low vision aids have been helpful for patients with nystagmus and blurred sight
Scanning CCTV called My Reader. This device can scan and reformat the text to display only one word or one line of text on the screen at one time.
The J Bliss VIP scanning software program scans and modifies the text size and spacing for easy reading.
Binocular aspheric reading spectacles provide a wide field of view to assist with reading.
Vision therapy saccadic tracking activities can improve the efficiency of tracking eye movement skills.
The use of a typoscope or plastic window cutout to display only one line of text on the page at a time can be very helpful.