Chiari Malformation: Introduction
Arnold-Chiari malformation is an uncommon neurological disorder that affects the cerebellum of the brain. The cerebellum is the lower area in the back of the brain that controls balance, motor control and muscle tone, in addition to a variety of other functions.
Arnold-Chiari malformation is also often referred to as Chiari malformation, and includes several grades of severity. Arnold-Chiari malformation is also sometimes called tonsillar herniation.
Arnold-Chiari malformation is caused by an abnormality of the skull, such as a small skull or malformed skull, which forces a part of the cerebellum to extend down below its normal position in the skull. In Arnold-Chiari malformation, the cerebellum pushes down into the spinal canal and puts pressure on the brain stem. The severity of Arnold-Chiari malformation varies greatly between individual cases and can result in a variety of symptoms. The most common symptom of Arnold-Chiari malformation is headache. Some people with mild cases of Arnold-Chiari malformation may have no symptoms.
Depending on the severity of the Arnold-Chiari malformation, the disorder can also cause vision problems, muscle weakness and dizziness. Disability and other potentially serious complications, such as paralysis and even death, may occur in some severe cases. For more details on symptoms and complications, refer to symptoms of Arnold-Chiari malformation.
Arnold-Chiari malformation is often congenital (present at birth). It is believed that Arnold-Chiari malformation may have a hereditary component and run in families.
Making a diagnosis of Arnold-Chiari malformation includes taking a thorough personal and family history, including symptoms, and completing a physical examination. This includes a neurological exam, which checks the functioning of the eight cranial nerves and such other neurological elements as level of consciousness, sensory responses, motor control, muscle tone and strength, reflexes and swallowing ability.
Diagnostic testing includes MRI, an imaging test done in the radiology setting that can reveal abnormalities of the brain and definitively diagnose Arnold-Chiari malformation. Another imaging test, CT of the brain may also be done.
It is possible that a diagnosis of Arnold-Chiari malformation can be missed or delayed because symptoms can mimic symptoms of other diseases and for a variety of other reasons. For more information on misdiagnosis, refer to misdiagnosis of Arnold-Chiari malformation.
Treatment of Arnold-Chiari malformation is generally provided by a neurosurgeon. Treatment plans vary depending on the severity of the condition and the presence of complications, among other factors. Treatment may include medications, physical therapy, modification of activities and surgery. For more information on treatment, refer to treatment of Arnold-Chiari malformation.
The prognosis for Arnold-Chiari malformation varies depending on the type and severity of the malformation. Some people may experience little to no problems during their lives. In other cases, there can be progressive and permanent damage to the nervous system. Surgery or multiple surgeries can help stop the progression of Arnold-Chiari malformation in some cases. In some very severe cases, Arnold-Chiari malformation can be fatal in infancy. ...more »
Chiari malformation (also called Arnold-Chiari
malformation) is a condition in which the cerebellum portion of the brain
protrudes down into the ... more about Chiari Malformation.
Chiari Malformation: Protrusion of the brain down the spinal column.
More detailed information about the symptoms,
causes, and treatments of Chiari Malformation is available below.
Chiari Malformation: Animations
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