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Chiari Malformation - What You Need To Know

Chiari Malformation - What You Need To Know

Provided By: Cleveland Clinic

What is Chiari malformation?

Chiari malformation is a condition in which brain tissue in the lower back part of your skull is forced into the spinal canal. Most of the time, this happens because of a structural problem, a misshaped or smaller-than-normal part of the skull. Because there is not enough room in the skull, part of the brain, specifically the cerebellum, grows downward into the spinal canal. This can cause compression on the brain at the base of your skull. Brain tissue in the spinal canal can block the flow of cerebrospinal fluid. This fluid cushions the brain and spinal cord, circulates nutrients and chemicals and removes waste products.

Who does Chiari malformation affect?

Chiari malformation can affect anyone. Females have a slightly higher chance of having a Chiari malformation than males.

In most cases, babies are born with the condition. However, sometimes Chiari malformations aren’t discovered until the teen years or adulthood when a brain scan is ordered for another reason. Although there is no cure for Chiari malformation, surgeons can treat or manage symptoms in most people.

How common is Chiari malformation?

Chiari malformation occurs in about one out of every 1,000 people. Because some people don’t have any symptoms or don’t show them until adolescence or adulthood, the condition may actually be more common.

Symptoms and Causes 

What causes Chiari malformation?

Chiari malformation has multiple causes. Chiari malformation is caused by a structural defect in the brain and spinal cord that happens while a baby is developing in the womb. Some investigators also believe that the structural defect in the skull (smaller than normal size in the area where the cerebellum sits) leads to the crowding and pressure on the brain that pushes it through the foramen magnum where the brain and spinal cord meet.

Because Chiari malformations have occurred in more than one family member, the disorder might also be inherited (passed down through families) in some cases.

Some researchers believe a lack of certain nutrients during pregnancy may play a role.

Chiari malformations are almost always present at birth, though symptoms may not develop until later in life. Very rarely, a Chiari malformation can develop in someone who was not born with the disorder. In these cases, the skull or spinal cord might change shape due to tumors, irregularities of the spine, or hematomas.

What are the symptoms of Chiari malformation?

Symptoms vary from person to person and range from no symptoms to mild to severe symptoms. In some people, symptoms are present at birth. In others, symptoms appear in late childhood or adulthood. Symptoms may also get better or worse at different points in time. Common symptoms include:

  • Headache pain: This is the most common symptom. Headache can start or worsen after coughing, sneezing, or straining and often occur at the back of the head. Pain may spread to the neck and shoulder. Pain is described as throbbing, stabbing, or sharp.
  • Balance and movement problems: Muscle weakness, coordination issues and numbness in the limbs can lead to problems with fine motor skills. Chiari malformation can also cause dizziness, vertigo, and balance problems.
  • Problems with hearing and vision: Some people hear a buzzing or ringing sound (tinnitus) and may have trouble hearing. Double vision (diplopia), blurred vision, abnormal eye movements (nystagmus), and sensitivity to light (photophobia) can also occur.
  • Trouble with eating, drinking, and speaking: Swallowing problems (dysphagia) can occur. Babies with Chiari malformation may vomit, gag or drool a lot. They may have trouble eating, and they may not be able to gain enough weight to develop properly.
  • Scoliosis: The spine can become curved, a condition called scoliosis.
  • Difficulty sleeping: Insomnia can occur, sometimes due to pain from headaches. Some people also experience sleep apnea (trouble breathing while sleeping).
  • Bladder and bowel issues: Loss of control over the bladder and bowel can result from Chiari malformation.
  • Other symptoms: Other symptoms include chronic fatigue, palpitations, fainting episodes, and tingling or burning sensations in fingers, toes, or lips.

To learn how we can help you or your loved one with a Chiari malformation, click here!