Chiari I Malformation
The UW Health Pediatric Neurosurgery program provides surgical care for children with Chiari malformation.
What is Chiari malformation?
Chiari malformation is a defect of the lower back portion of the brain that extends into the spinal canal. This structural defect causes the cerebellum (the part of the brain that controls balance) and brain stem to be pushed downward.
Pressure resulting from the Chiari malformation disrupts the flow of cerebrospinal fluid, often leading to symptoms listed below.
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| Chiari malformation affects the portion of the brain that extends into the spinal canal. |
- Headaches
- Pain in the neck, shoulders and arms
- Problems with coordination and balance
- Weakness and numbness
- Spinal cord cyst
Diagnosis of Chiari Malformation
Chiari malformation often goes undiagnosed. Some children may have symptoms that cause them to get a MRI, which reveals Chiari malformation. Another possible sign of Chiari malformation is scoliosis.
Treatment
Medication can help with some symptoms. Brain surgery is dependent on the severity of the symptoms and is sometimes an option to correct the structural defect, prevent further damage to the central nervous system and relieve symptoms. During surgery, doctors create space at the base of the brain sufficient to allow for the normal flow of cerebrospinal fluid.

