Chiari malformation

A Chiari malformation occurs when brain tissue extends outside of the skull and into the spinal cord. The cerebellum is a lower part of the brain that controls balance, coordination, and muscle movement. Normally, the cerebellum sits above an opening in the skull where the spinal cord passes through, called the foramen magnum. When part of the cerebellum extends below the foramen magnum and into the upper spinal canal, a Chiara malformation is present. There are several different types of Chiari malformations that are classified by the severity of the disorder and the part of the brain that is affected.

Causes and Risk Factors

  • Most often caused by structural defects in the brain and spinal cord that occur during fetal development
  • Excessive draining of spinal fluid due to traumatic injury, disease, or infection
  • May be hereditary


Many people with Chiari malformation have no signs or symptoms and don’t require treatment. However, depending on the severity of the condition, there are some common symptoms:

  • Headaches, especially after coughing, sneezing, or straining
  • Severe neck pain
  • Dizziness and balance problems
  • Blurred or double vision
  • Difficulty swallowing, which may cause gagging, choking, or vomiting
  • Sleep apnea
  • Loss of sensation or tingling in the hands and arms
  • Developmental delays


Treatment for Chiari malformation depends on the severity of the condition and symptoms. If no symptoms are present, your doctor will likely recommend no further treatment beyond monitoring with regular examinations. If headaches are the main symptoms, medications may be prescribed by your doctor. When more serious symptoms are present, surgery is usually necessary to relieve pressure on the spinal cord.