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Visual Snow Syndrome: What Is It, Causes & How to Treat

Visual snow syndrome (VSS) is a condition characterized by the presence of static or “snowy” visual disturbances. Individuals with visual snow syndrome may see flickering lights, zigzag patterns, or other visual “noise” in their field of vision.

Causes of Visual Snow Syndrome

The exact cause of visual snow syndrome is unknown. However, it is thought to be linked to changes in how the brain processes visual information. Some experts believe that visual snow syndrome is closely related to the following conditions:

Thalamocortical Dysrhythmia

Thalamocortical dysrhythmia is characterized by abnormal electrical activity in the thalamus and cortex. This abnormal activity can cause several cognitive and perceptual problems, including visual snow.

The thalamus is a small region of the brain that plays an important role in processing sensory information. Thalamocortical dysrhythmia is thought to cause visual snow syndrome by disrupting the regular communication between the thalamus and cortex.

This disruption can lead to changes in how the brain processes visual information, resulting in the perception of static or “snowy” visual disturbances.

Hallucinogen Persisting Perception Disorder (HPPD)

This is a condition that can occur after taking certain drugs, such as lysergic acid diethylamide (LSD). People with HPPD may experience visual disturbances, such as visual snow, as well as other perceptual changes.

Other Causes

Visual snow syndrome may present itself as a symptom of other medical conditions, including these:

  • Persistent migraine aura (PMA) 
  • Brain injury 
  • Optic neuritis

Symptoms of Visual Snow

Visual snow syndrome is characterized by the presence of static or “snowy” visual disturbances. These visual disturbances may appear in the following forms:

  • Sensitivity to light
  • Floaters
  • Night blindness
  • Blurry vision
  • Starbursts
  • Flashing lights
  • Glare
  • Double vision
  • Palinopsia (seeing the image after it is no longer present)

According to experts, to be diagnosed with visual snow syndrome, you must experience these visual disturbances daily for at least three months.

Complications of Visual Snow

While visual snow syndrome is not a severe condition, it can lead to significant distress and impair your quality of life. In some cases, visual snow syndrome may also be associated with the following complications:

Migraines

People with visual snow syndrome often experience migraines. These migraines may be accompanied by other symptoms, such as nausea, vomiting, and sensitivity to light.

Depression

Visual snow syndrome can lead to depression. The inability to function normally or constant visual disturbances may be the cause of this.

Anxiety

Visual snow syndrome can also cause anxiety. This may be because of the fear of being unable to see properly or the continual visual disturbances.

Vertigo

Some people with visual snow may experience vertigo. Symptoms of vertigo include nausea and dizziness due to the sensation of spinning or whirling.

These complications can significantly impair your quality of life.

Risk Factors for VSS

There are several risk factors for visual snow syndrome, including these:

  • Migraines: Visual snow syndrome is more common in migraine sufferers.
  • Drug use: People who have used certain drugs, such as LSD, are at increased risk for VSS.
  • Brain injury: People who have suffered a brain injury are more likely to develop visual snow syndrome.

Several disorders share symptoms with visual snow syndrome, such as these:

Tinnitus

The condition of tinnitus causes ringing, buzzing, or roaring in the ears. It is a prevalent disorder, affecting about 11.9 to 30.3 percent of the population.

Tinnitus is often comorbid with visual snow syndrome. 

Prolonged Migraine Aura

Approximately 12 percent of the population suffers from migraines. Visual snow syndrome often co-occurs with migraines.

There are migraines that last for a few hours, and others that last for days or even weeks. Prolonged migraines are a type of migraine that lasts for over 72 hours.

Visual Aura

A visual aura is a type of visual disturbance often seen in people with migraines, which typically lasts for less than an hour.

A visual aura may precede or accompany a migraine. It usually begins in the center of your field of vision and then spreads outward. The symptoms can be similar to visual snow and may include the following:

  • Flashing lights
  • Zigzag lines
  • Blind spots

Diagnosis of VSS

Diagnosis can be difficult because the symptoms of visual snow syndrome are similar to those of other conditions.

To diagnose VSS, your doctor will need to confirm the following and exclude other possible causes of your symptoms:

  • You must have had the visual disturbances for at least three months.
  • The visual disturbances must be constant, meaning they occur every day.
  • You must not have any other condition that could explain your symptoms.

Additionally, you must have two of the following visual symptoms:

  • Photophobia (light sensitivity)
  • Nyctalopia (night blindness)
  • Palinopsia (after-images or trailing images)
  • Entoptic phenomena (floaters or blue field entoptic phenomenon)

In addition to a physical exam, the doctor will order tests to rule out any underlying conditions. These may include the following:

  • Blood tests
  • Imaging tests
  • Ophthalmologic examination

Treatment for Visual Snow Syndrome

There is no cure for visual snow syndrome. However, you can get relief from symptoms and improve your quality of life with some treatments. 

Some studies show that amitriptyline, a tricyclic antidepressant, can help reduce the symptoms of visual snow syndrome.

These other medications may be helpful:

  • Valproate
  • Sertraline
  • Baclofen
  • Verapamil 

Vision therapy may also be beneficial. This type of rehabilitation helps train your brain to process visual information more effectively.

Prevention

There is no known prevention for visual snow syndrome. However, you can reduce your risk of developing the condition by avoiding migraine triggers and treating migraines early.

Additionally, you should avoid drug use and seek prompt treatment if you suffer a head injury.

Visual Snow Syndrome FAQs

Is visual snow serious?

While visual snow is not typically considered a serious condition, it can be very debilitating for those who experience it. In addition to visual disturbances, people with visual snow often report symptoms like fatigue, anxiety, and depression. 

How rare is visual snow?

The exact prevalence of visual snow is unknown. However, it is thought to be rare.

Can visual snow go away?

While there is currently no cure for visual snow, there are some treatments that may help lessen the symptoms. Certain medications and vision therapy may help.

References

  1. Visual Snow Syndrome. (2019). National Organization for Rare Disorders.

  2. Visual Snow Syndrome Causes Becoming Clearer. (March 2022). Medicine, Nursing and Health Sciences.

  3. Visual Snow: A Thalamocortical Dysrhythmia of the Visual Pathway? (June 2016). Journal of Clinical Neuroscience.

  4. Visual Snow. (January 2022). American Academy of Ophthalmology.

  5. Episodic Visual Snow Associated With Migraine Attacks. (November 2019). JAMA Neurology.

  6. The Psychiatric Symptomology of Visual Snow Syndrome. (July 2021). Frontiers in Neurology.

  7. Visual Snow in Hallucinogen-Persisting Perception Disorder. (November 2020). Ophthalmologe.

  8. Visual Snow Syndrome, the Spectrum of Perceptual Disorders, and Migraine as a Common Risk Factor: A Narrative Review. (September 2021) Headache: The Journal of Head and Face Pain.

  9. Migraine Prevalence in Visual Snow With Prior Illicit Drug Use (Hallucinogen Persisting Perception Disorder) Versus Without. (May 2021). European Journal of Neurology.

  10. On Perception and Consciousness in HPPD: A Systematic Review. (August 2021). Frontiers in Neuroscience.

  11. Visual Snow Syndrome. (February 2020). Neurology.

  12. Visual Snow Syndrome: A Case Report and New Treatment Option. (2018). Clinical Medical Reviews and Case Reports.

  13. Insights Into Pathophysiology and Treatment of Visual Snow Syndrome: A Systematic Review. (June 2020). Progress in Brain Research.

  14. Ever See Spots or Dots? Here’s All You Need to Know About Visual Snow Syndrome. (March 2022). Cosmopolitan.

  15. What Is the Actual Prevalence of Migraine? (May 2018) Brain and Behavior.

  16. Treatment Effects and Comorbid Diseases in 58 Patients With Visual Snow. (July 2019). Neurology.

  17. Visual Snow Syndrome as a Network Disorder: A Systematic Review. (October 2021). Frontiers in Neurology.

Last Updated August 9, 2022

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