Opsoclonus Myoclonus Syndrome (OMS)

What is opsoclonus myoclonus syndrome?

Opsoclonus myoclonus syndrome (OMS) is a neurological disorder that is characterized by inflammation in the brain. It has a severe and abrupt onset and has the potential to become chronic. 

What are the symptoms of opsoclonus myoclonus syndrome?

Symptoms include:

• Repeated, random, and rapid eye movements
• Issues with walking and standing
• Spasms in the muscles in the legs and arms
• Tremors in the hands
• Sleep disturbances (insomnia)
• Behavior disturbances (irritability, crying, rage)
• Speech problems
• Vomiting
• Decreased muscle tone

What causes opsoclonus myoclonus syndrome?

The most common cause is a tumor that pushes the immune system to attack the nervous system. There are other causes as well, such as viral infections. 

How is opsoclonus myoclonus syndrome diagnosed?

Doctors will look for the characteristic symptoms, use a spinal tap, and perform a clinical evaluation, as no diagnostic test exists yet. They will also look for the underlying cause, whether it is a tumor or infection. 

What are the treatments for opsoclonus myoclonus syndrome?

Aggressive immunotherapy is used to treat OMS, and it is most effective if utilized early. This treatment will last for about one to two years. If a tumor is the cause, surgery will be needed to remove it. 

Where can I find out more about opsoclonus myoclonus syndrome?

• • • NORD
    • NIH
    • Children’s Hospital of Philadelphia