Chiari I malformation (key-AR-ee mal-for-MAY-shun) happens when the cerebellum — the part of the brain that controls coordination and muscle movement — pushes down through the hole in the bottom of the skull (called the foramen magnum) .

Many kids with Chiari I malformation have no symptoms. Children without symptoms just need regular follow-up appointments with their healthcare provider. They may require a follow-up brain MRI (a medical imaging test that makes detailed pictures of the brain) to check for any changes. Surgery usually isn't needed.

If symptoms occur, they generally don't show up until late childhood or the teen years, usually from pressure on the brain and nerves. Younger kids under age 3 might have feeding problems or sleep apnea.

Here's how to care for your child after they are diagnosed with Chiari I malformation.

Follow your healthcare provider's instructions for:

• Making all follow-up appointments
• Going for all recommended tests, such as X-rays or MRIs
• Avoiding any activities, such as gymnastics, wrestling, and contact sports, if recommended

Your child:

• Gets a headache (especially after sneezing, coughing, or straining during sports activities or while trying to take a poop)
• Has balance problems, neck pain, or dizziness
• Has vision problems (such as double or blurred vision, or light sensitivity)
• Has trouble using their hands as they usually do
• Has numbness or tingling of the hands and feet
• Has a change in urine (pee) or bowel (poop) habits
• Has trouble swallowing
• Is hoarse when talking
• Snores loudly with pauses in breathing during sleep (sleep apnea)

Your child has:

• A head or a neck injury
• Any of these symptoms that could mean there is too much pressure on a part of the brain:
  • Severe headache or neck pain
  • Trouble breathing
  • Passes out

What causes Chiari I malformation? A baby can be born with it or develop it in the first few years of life. Less often, it can happen later in life from an injury, infection, or other medical problems. Chiari I malformation also can run in families. It may have a genetic cause.

What medical issues can occur in children with Chiari I? Children with Chiari I malformation may develop:

• Headaches, usually on the back of the head, near the base of the skull.
• Syringomyelia (ser-in-go-my-ILL-ee-uh), a fluid-filled space within the spinal cord.
• Hydrocephalus (hi-droh-SEF-eh-less), a buildup of spinal fluid within the brain.
• Scoliosis, curvature of the spine.
• Sleep apnea, hoarseness, speech and swallowing problems, and nystagmus (beating of the eyes back and forth). These issues come from pressure on the brainstem and on nerves of the face and head.

Treatment can help kids who have any of these issues. For children with severe symptoms, doctors often recommend a surgery called posterior fossa decompression. This surgery makes more space for the cerebellum and lowers pressure on the spinal cord.