As the lower part of the brain, the cerebellum, protrudes into the spinal canal, it causes Chiari malformation. When the cerebellum is pushed downward, it can compress the brainstem and the spinal cord and cause various symptoms. The cerebellum coordinates movement, balance, and posture.
What causes Chiari malformation?
The exact cause of Chiari malformation is not fully understood. However, some possible causes or risk factors include:
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Genetic factors. Some people may inherit a tendency to have a smaller or misshapen skull that does not have enough room for the brain. This can result in the cerebellum being pushed downward into the spinal canal.
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Congenital factors. Some people may develop Chiari malformation during fetal development due to abnormal growth or formation of the skull, brain, or spinal cord. This can be influenced by environmental factors such as maternal nutrition, infection, or exposure to toxins.
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Acquired factors. Some people may develop Chiari malformation later in life due to injury, infection, surgery, or other conditions that affect the skull, brain, or spinal cord. This can cause increased pressure in the head or fluid buildup in the brain (hydrocephalus) that can push the cerebellum downward.
What are the symptoms of Chiari malformation?
The symptoms of Chiari malformation vary from person to person and depend on the type and severity of the condition. Some common symptoms include:
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Headache. This is the most common symptom of Chiari malformation. The headache usually occurs at the back of the head and may worsen with coughing, sneezing, straining, or bending forward.
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Neck pain. This may be caused by the pressure or tension on the neck muscles and nerves due to the downward displacement of the cerebellum.
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Dizziness or vertigo. This may be caused by the disruption of the balance and coordination functions of the cerebellum.
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Numbness or tingling in the arms or legs. This may be caused by the compression or damage of the spinal cord or nerve roots due to the downward displacement of the cerebellum.
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Weakness or stiffness in the arms or legs. This may be caused by the impairment of the motor functions of the brainstem or spinal cord due to the downward displacement of the cerebellum.
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Difficulty swallowing or speaking. This may be caused by the involvement of the cranial nerves that control these functions due to the downward displacement of the cerebellum.
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Vision problems. This may include blurred vision, double vision, nystagmus (involuntary eye movements), or ptosis (drooping eyelid) due to the involvement of the cranial nerves that control these functions due to the downward displacement of the cerebellum.
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Breathing problems. This may include sleep apnea (pauses in breathing during sleep), snoring, or central apnea (failure to breathe due to brainstem dysfunction) due to the compression or damage of the brainstem due to the downward displacement of the cerebellum.
How is Chiari malformation diagnosed?
Your doctor will ask about your symptoms and medical history, as well as perform a physical examination. Some tests may also be ordered to confirm the diagnosis and to determine the extent and impact of your condition. For example:
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A magnetic resonance imaging scan (MRI) to produce detailed images of your brain and spinal cord and measure the size and position of your cerebellum and brainstem.
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A computed tomography scan (CT) to create cross-sectional images of your skull and spine and detect any abnormalities such as bone deformities or fluid buildup.
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A cerebrospinal fluid (CSF) analysis to collect and examine a sample of fluid from your spinal canal and check for signs of infection, inflammation, or increased pressure.
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An electroencephalogram (EEG) to measure the electrical activity of your brain and detect any abnormalities such as seizures or brain waves.
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A sleep study to monitor your breathing, heart rate, oxygen level, and brain activity during sleep and diagnose any sleep disorders such as sleep apnea.
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A nerve conduction study (NCS) or electromyography (EMG) to test the function and response of your nerves and muscles and detect any damage or weakness.
How is Chiari malformation treated?
The treatment for Chiari malformation depends on the type and severity of the condition, as well as your symptoms and preferences. Some common treatments include:
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These include over-the-counter pain relievers such as ibuprofen or acetaminophen, prescription muscle relaxants such as baclofen or tizanidine, or prescription anti-nausea medications such as ondansetron or metoclopramide.
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Infection, inflammation, or elevated pressure may be treated or prevented with medication. Prescription antibiotics like ciprofloxacin or amoxicillin, prescription anti-inflammatory drugs such as corticosteroids or nonsteroidal anti-inflammatory drugs (NSAIDs), or prescription diuretics such as acetazolamide or furosemide are among them.
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In order to restore normal cerebrospinal fluid flow, surgery is performed to decompress the brainstem and spinal cord. In order to create more space for the cerebellum and brainstem, a small piece of bone is removed from the back of the skull and sometimes from the spine. Additionally, a patch may be inserted into the dura mater (protective membrane covering the brain and spinal cord) during surgery.
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A procedure aimed at draining excess fluid from the brain and spinal cord. The surgery involves inserting a thin tube called a shunt into the ventricles (the fluid-filled spaces in the brain) or the spinal canal and connecting it to another part of the body such as the abdomen or chest where the fluid will be absorbed.
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An operation to correct structural abnormalities of the skull, spine, or brain, including reshaping or fusing bones, repairing or replacing valves, or removing tumors or cysts.
How can you prevent Chiari malformation?
There are some steps you can take to reduce your risk of developing complications or worsening your Chiari malformation. These steps include:
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Following your doctor's treatment plan and getting regular check-ups.
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Coughing, sneezing, straining, bending forward, lifting heavy objects, or blowing your nose can increase head pressure.
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Boxing, football, rugby, and skiing are all contact sports that can cause head trauma.
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Practice relaxation techniques such as meditation, yoga, or deep breathing to manage your stress levels.
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Maintaining a balanced diet with low sodium and high potassium, calcium, magnesium, and vitamin D.
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Staying hydrated and drinking plenty of water.
Chiari malformation is a rare but serious condition that can affect the quality of your life. However, with proper diagnosis, treatment, and prevention, symptoms can be managed and complications can be avoided.
