CausesChiari malformation can be caused by structural problem/s with the:
- Spinal canal
TypesThere are 4 types and are categorized by how much brain tissue protrudes into the spinal canal.
Type IThis is the adult version and is also the most common. It is usually first noticed and discovered from an examination for something else. Most individuals don’t realize that they have Chiari malformation unless the symptoms are severe. With Type I a part of the brain, specifically the cerebellar tonsils settle into the foramen magnum.
Type IIType II is also known as Arnold-Chiari malformation. This is the pediatric version. Symptoms are more severe with Type II because more brain tissue comes through. With this type, the cerebellar tonsils and some of the brainstem protrude. With Type II myelomeningocele, which is a form of spina bifida is a concern. What happens is the vertebrae and spinal canal do not close correctly before birth, so the spinal cord has no protection.
Type IIIThis type also affects children and is more severe than types 1 or 2. Here a significant portion of the brain, including the cerebellum and the brainstem protrude all the way through the foramen into the spinal canal.
Type IVType IV is the most severe form. With this type, the brain does not develop properly.
SymptomsThe symptoms vary based on the type and severity. The most common symptom is a headache. Individuals with a Chiari malformation usually have headaches in the occipital region of the brain. This is the back of the head, right where the skull joins the cervical spine/neck. The headaches can be aggravated being in certain positions and actions, tilting the head back, and coughing. Typical symptoms include:
- Balance problems
- Difficulty with fine motor skills
- Trouble swallowing
- Vision problems