Nystagmus: Symptoms, Causes, and Treatments

Nystagmus is a condition in which the eyes make uncontrolled, repetitive movements. These movements can be slow or fast, side-to-side (horizontal), up-and-down (vertical), or even in a circular (rotary) motion.

These involuntary eye movements can affect vision, depth perception, and balance. In some people, it can also cause a noticeable head turn or tilt, as they try to position their eyes in a way that makes the movements less severe.

While some people are born with nystagmus (congenital nystagmus), others develop it later in life (acquired nystagmus) due to an underlying health condition or neurological problem. Understanding the symptoms, causes, and available treatments is key to managing the condition and preserving vision.

Types of Nystagmus

Nystagmus can be classified in several ways based on when it appears and the direction of the eye movements:

1. Congenital (Infantile) Nystagmus
   

   • Appears within the first few months of life.
     
     
   • Often linked to inherited eye conditions or developmental issues.
     
     
   • Eye movements are usually horizontal.
     
     
   • Children with congenital nystagmus often adapt and may not notice major vision changes.
     
     

2. Acquired Nystagmus
   

   • Develops later in life, often due to an underlying medical or neurological condition.
     
     
   • May cause more noticeable vision disturbance because it develops after normal vision has been established.
     
     

3. Jerk Nystagmus
   

   • The eyes drift slowly in one direction, then quickly “jerk” back to the starting point.
     
     

4. Pendular Nystagmus
   

   • Eye movements are smooth and equal in both directions.
     
     

5. Manifest Nystagmus
   

   • Always present, regardless of whether both eyes are open or closed.
     
     

6. Latent Nystagmus
   

   • Appears only when one eye is covered.
     
     

Common symptoms of Nystagmus

While symptoms vary depending on the type and severity, common signs include:

• Rapid, uncontrolled eye movements – horizontal, vertical, or circular.
  
  
• Shaky or blurred vision – objects may appear to “move” or “jump”.
  
  
• Difficulty focusing – especially on distant or small objects.
  
  
• Head tilt or turn – to find a “null point” where eye movement is reduced and vision is clearer.
  
  
• Light sensitivity (photophobia) – discomfort in bright sunlight or artificial lighting.
  
  
• Balance and coordination problems – especially if linked to inner ear disorders.
  
  
• Eye strain – from constant effort to stabilise vision.
  
  

Causes of Nystagmus

The causes differ depending on whether it is congenital or acquired.

1. Causes of Congenital Nystagmus

• Genetic eye conditions – e.g., albinism, congenital cataracts.
  
  
• Optic nerve hypoplasia – underdevelopment of the optic nerve.
  
  
• Retinal diseases – affecting the light-sensitive layer at the back of the eye.
  
  
• Neurological development disorders – issues in the brain areas controlling eye movement.

2. Causes of Acquired Nystagmus

• Neurological disorders – multiple sclerosis, brain tumour, stroke, or head injury.
  
  
• Inner ear problems – vestibular neuritis, Ménière’s disease.
  
  
• Medication side effects – anti-seizure drugs, sedatives, alcohol toxicity.
  
  
• Eye diseases – cataracts, macular degeneration.
  
  
• Vitamin deficiencies – especially B12 or thiamine in severe cases.
  
  

How Nystagmus is Diagnosed?

An accurate diagnosis is essential for effective treatment. At Clarity Eye Surgeons, we follow a step-by-step approach:

1. Comprehensive Eye Examination

This is the first step in evaluating any eye-related problem. It involves checking visual clarity (sharpness of vision), assessing eye structures such as the cornea, lens, retina, and optic nerve, and examining eye movement patterns. The doctor also looks for signs of refractive errors (like nearsightedness or farsightedness), cataracts, glaucoma, or retinal conditions that may affect vision.

2. Visual Function Tests

These tests evaluate how well the eyes focus, follow moving objects, and work together as a team. They may include tests for tracking, depth perception, peripheral vision, and contrast sensitivity. Such assessments are important to detect conditions like strabismus (eye misalignment), amblyopia (lazy eye), or coordination problems that affect reading, balance, and daily activities.

3. Neurological Assessment

If eye problems seem related to the brain or nervous system, a neurological evaluation may be recommended. This could involve testing reflexes, muscle strength, coordination, and nerve function. The purpose is to rule out or confirm conditions like multiple sclerosis, stroke, or nerve palsies that can interfere with eye control and movement.

4. Eye Movement Recording (Electronystagmography or Videonystagmography)

These specialized tests are used to study involuntary eye movements, known as nystagmus, which often relate to balance disorders or neurological problems. Using electrodes around the eyes (ENG) or video goggles (VNG), the equipment records the direction, speed, and rhythm of eye movements. This helps identify whether the issue originates from the inner ear (vestibular system) or the brain. 

5. Imaging Tests (MRI or CT Scan)

In cases where structural issues are suspected, doctors may order brain imaging. MRI (Magnetic Resonance Imaging) provides detailed images of the brain, optic nerves, and inner ear structures, while a CT scan gives a quick view of bone and tissue structures. These imaging tests help detect tumors, injuries, inflammation, or vascular abnormalities that could affect vision and eye movement.

Treatment options for nystagmus

Treatment depends on the underlying cause, type, and severity of symptoms. While nystagmus cannot always be cured, many approaches can reduce symptoms and improve quality of life.

1. Correcting Vision Problems

Glasses or contact lenses – to improve clarity and reduce strain.