Pendular nystagmus

Pendular Nystagmus

Pendular nystagmus is a type of eye movement disorder characterized by oscillations of the eyes that are smooth and pendular, meaning they move with equal speed in both directions. Unlike the more common jerk nystagmus, where eye movements are quick in one direction and slow in the other, pendular nystagmus involves a regular, rhythmic motion without distinct fast or slow phases. This condition can affect one or both eyes and may result in impaired vision and reduced visual acuity.

Causes

Pendular nystagmus can have various causes, ranging from congenital conditions to acquired ones later in life. Congenital pendular nystagmus often appears in infancy and may be associated with other conditions such as albinism, congenital cataracts, or achromatopsia. Acquired pendular nystagmus may develop as a result of neurological disorders, such as multiple sclerosis (MS), or as a side effect of certain medications.

Symptoms

The primary symptom of pendular nystagmus is the involuntary eye movement itself. Individuals with this condition may also experience:

• Blurred vision
• Reduced visual acuity
• Difficulty focusing on stationary objects
• Oscillopsia (the sensation that stationary objects are moving)
• Headaches and dizziness in some cases

Diagnosis

Diagnosis of pendular nystagmus involves a comprehensive eye examination, including observation of the eye movements. Additional tests may include:

• Visual acuity tests
• Electrooculography (EOG) to measure eye movements
• Magnetic resonance imaging (MRI) to identify any underlying neurological conditions
• Visual evoked potentials (VEP) to assess the visual system's response to stimuli

Treatment

Treatment for pendular nystagmus focuses on addressing the underlying cause, if known, and may include:

• Corrective glasses or contact lenses to improve visual acuity
• Medications to reduce the amplitude of eye movements in some cases
• Surgery, in rare instances, to modify the position of the eye muscles
• Vision therapy to help manage symptoms

In cases where pendular nystagmus is caused by a neurological condition, treatment of the underlying condition may help alleviate the nystagmus.

Prognosis

The prognosis for individuals with pendular nystagmus varies depending on the underlying cause and the effectiveness of treatment. While the condition may significantly impact vision, many people are able to manage their symptoms effectively with appropriate treatment and support.

See Also

• Nystagmus
• Visual impairment
• Eye movement disorders
• Neurological disorders