Med. Term. Final Draft
October 8, 2012
Chiari Malformation
Chiari Malformation is a condition in which brain tissue protrudes into your spinal canal. This happens when part of your skull is small or misshaped, pressing on your brain and pushing it downward. Chiari Malformation is not common, but throughout time imaging tests have improved, leading to more frequent diagnosis.
Chiari Malformation is categorized into the following four types: Chiari I, Chiari II, Chiari III, and Chiari Malformation IV. Many people with Chiari Malformation have no signs or symptoms and do not need treatment. However, depending on the type and severity, Chiari can cause a number of problems.
The more common types of Chiari Malformation are: type I (adult) and type II (pediatric). The classic symptom for patients suffering from chiari Malformation type I is severe headache. Sudden coughing, sneezing or straining usually brings on the headaches. Other symptoms patients may experience are: neck pain, unsteady gait, poor hand coordination, numbness in hands and feet, dizziness, vision problems, and slurred speech. Chiari Malformation IV presents with more severe symptoms such as paralysis, hearing loss and vision loss that is irreversible.
Chiari Malformation occurs when the section of the skull housing the cerebellum is to small or is deformed, putting pressure on and crowding the brain. The lowermost portions, or the cerebral spinal tonsils, are displaced into the upper spinal canal. When the cerebellum is pushed into the upper spinal canal, it can interfere with the normal flow of cerebrospinal fluid (CSF) that protects your brain and spinal cord. This impaired circulation of CSF can lead to the blockage of signal transmitted from your brain to your body, or to a buildup of spinal fluid in the brain or spinal cord. This pressure upon the spinal cord or lower