Chiari I malformation (key-AR-ee mal-fore-MAY-shun) is 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. This hole is called the foramen (fer-AY-men) magnum. Usually
just the spinal cord passes through the foramen magnum.
Many kids with Chiari I malformation have no symptoms. Treatment can help kids
who do have them.
What Are the Signs & Symptoms of Chiari I Malformation?
Some people with Chiari I malformation never have any symptoms. If symptoms do
happen, they usually don't show up until late childhood or the teen years.
Signs and symptoms can include:
after sneezing, coughing, or straining)
poor hand coordination
numbness and tingling of the hands and feet
change in bladder (pee) or bowel (poop) habits
Sometimes, children with Chiari I malformation can also have:
a syringomyelia (ser-in-go-my-ILL-ee-uh): a fluid-filled space within the spinal
(hi-droh-SEF-eh-less): a buildup of spinal fluid in the spaces deep within the brain
sleep apnea: periods when breathing stops during sleep
There are four different types of Chiari malformation (I, II, III, and IV). Chiari
I is the most common.
Doctors don't know exactly what causes Chiari I malformation. A baby can be born
with Chiari I malformation or it can develop in the first few years of life. Less
often, the malformation can happen later in life from trauma, infection, or other
Chiari I malformation can run in families. So it may have a genetic
Chiari malformations happen when the space for the cerebellum is smaller than normal
or has an unusual shape. This squeezes part of the cerebellum down through the foramen
magnum. If this puts pressure on the cerebellum and spinal cord, it can lead to symptoms.
How Is Chiari I Malformation Diagnosed?
Chiari I malformations usually don't cause symptoms. So many aren't found until
an imaging study of the brain or upper spine is done for a different reason.
How Is a Chiari Malformation Treated?
For kids without symptoms, doctors usually recommend getting follow-up MRIs
to check for any changes. Surgery is not usually needed.
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.
Kids with related problems (such as syringomyelia, hydrocephalus, sleep apnea,
or scoliosis) may need medical treatment for those conditions.
Some doctors recommend that kids with Chiari I malformation avoid certain activities
like gymnastics, wrestling, and contact sports.
What Can Parents Do?
Many kids with Chiari I malformation do not have symptoms and never need treatment.
But call your doctor right away if your child does show any symptoms, such as headache,
balance or coordination problems, changes in pee or poop habits, or voice changes.
To help your child stay healthy, follow your doctor's instructions for:
making and keeping all follow-up appointments
going for all recommended studies, such as X-rays or MRIs