The term nystagmus refers to a very rapid, lateral (side-to-side) movement of the eyeball. Everyone experiences a brief instance of it at some point in their life, typically the result of being overtired or straining to see something. However, any regular instances of nystagmus should generate an immediate call to an optometrist.
Nystagmus is divided into three different categories or stages:
- Infantile: While newborns experience nystagmus regularly as their eye muscles strengthen and their vision becomes more clear, nystagmus should be largely gone by month three. If you see regular nystagmus in your infant after the first month or so, let your pediatrician know so s/he can check into it or refer you to a pediatric optometrist for further evaluation.
- Spasmus Nutans: If nystagmus is noticed in children between the ages of two to eight years, it is called spasmus nutans. Children with spasmus nutans are divided into two groups, those with normal vision/brain function and those who have vision or neural issues. Treatment is determined accordingly.
- Acquired: If nystagmus shows up later on in childhood or adulthood, it is considered acquired nystagmus. This type of nystagmus is not usually congenital (stemming from your genetic makeup), but can be the result of some type of developed impairment, traumatic brain or eye injury, or even alcohol/drug use.
It’s interesting to note that while nystagmus is highly visible and noticeable to an onlooker who can witness the notable vibration/jiggling of the eyeballs, the person experiencing nystagmus is often unaware. This is especially true for children.
Often, the experience of nystagmus means having blurred or unfocused vision, but it doesn’t necessarily mean the visual world looks like it’s shaking or vibrating.
Nystagmus: Symptoms, Causes, & Treatment
Frequent or regular nystagmus almost always indicates potential vision loss and a diagnosis may also reveal a separate eye or medical condition that needs to be evaluated.
As we mentioned, nystagmus refers to rapid and uncontrolled eye movement. It can almost seem as if the person’s eyeballs are vibrating or jiggling. The motion typically takes place from side to side, but not always. You may also notice up and down motions, or the eyes may go around in circles.
Other symptoms include:
- Tilting the head or nodding it in various directions to see clearly
- Objects appear shaky or blurry
- Light sensitivity
- Difficulty seeing at night (night blindness)
- Trouble with balance
If you notice these symptoms in yourself or a family member, contact their pediatrician or eye doctor to schedule an appointment.
As we mentioned, nystagmus can occur whenever weak muscles, fatigue, eye strain, etc. are at play. However, more than very occasional nystagmus is typically a symptom that something else is wrong.
There are multiple causes of congenital and even acquired nystagmus. The most common fall into the former category and include:
Lack of muscle/nerve development and control
If there is any lack of muscle or nerve development and control, such as weak eye muscles or trouble with connections between the optic nerve and the brain, you can experience nystagmus. For example, nystagmus is often an early sign of a lazy eye – with the eye-straining to see and moving back-and-forth as it tracks an image before it gives up and rolls out of focus again.
It can also be a symptom of malformed muscles, nerves, or structures that support vision and eye control.
Visual impairment is very common for people with albinism (lack of skin pigment), and nystagmus is one of those. In most cases, your baby would be diagnosed with albinism immediately or very early on, in which case you would be referred to a pediatric optometrist to regularly monitor your child’s vision.
Severe nearsightedness or astigmatism
If you or one of your children has a very high refractive error (more dramatic nearsightedness or astigmatism) nystagmus is evidence of the hard work one or both eyes are doing to help him/her see.
Inflammation of the inner-ear
In medical terms, the vestibular system and the oculomotor nuclei are interconnected. This means that the nerves that control both your sense of balance (the vestibular system) and the nerves that control the muscular function of the eye (oculomotor) are connected. As a result, any inflammation of the inner-ear can negatively compromise eye function, leading to nystagmus.
Your optometrist knows to look for this connection if other, obvious causes, don’t make themselves known and will either refer you or your child to a general physician or an ear-nose-throat (ENT) specialist for further diagnosis.
If cataracts are causing diminished vision, nystagmus is a sign. Ideally, cataracts would be immediately noted in an annual eye exam. If, however, you’ve been skipping eye exams altogether, your straining eyes are a sign it’s time to schedule an appointment.
Diseases of the central nervous system
Any diseases of the central nervous system can affect any other part of the nervous system, including the ocular nerves or nerves that control your eye muscles.
Medication side effects
Medications for epilepsy can cause nystagmus, and those drugs are often used to treat non-epilepsy conditions such as migraines, neuropathic pain disorders, and bipolar disorder. Your doctor will review current medications and take them into consideration to see if they may be contributing to nystagmus symptoms.
Those are the most common causes of nystagmus. There is also a long list of other things that can cause the conditions such as:
- Eye diseases
- Malformed or underdeveloped optic nerve
- Malformed structure that forms the pupil
- Traumatic brain/eye injury
- Alcohol or drug abuse
- Optic nerve and retina disorders
- Brain tumor (very rare)
- Fetal alcohol syndrome
The treatment for nystagmus will vary depending on the diagnosis. Obviously, the first line of defense is managing and treating any underlying medical causes of the condition. This will create a partnership between your general physician and your optometrist and/or ophthalmologist to help you manage and treat the condition(s).
If weak eye muscles or nerve connections are part of the problem, we can use specific exercises, like “eye physical therapy,” to strengthen both the muscles in the eye(s) as well as the connection between the eye(s)/optic nerve/brain. Finally, corrective lenses (eyeglasses and/or contacts) or surgery may further rectify vision to reduce or eliminate nystagmus.
The key is to schedule an appointment with your optometrist for a comprehensive eye exam, and s/he’ll take it from there. Noticing episodes of nystagmus in your child, yourself, or a loved one? Contact the incredible team at Atlantic Eye Institute to schedule an appointment.