What is Chiari malformation?
Chiari malformation includes a complex group of disorders characterized by herniation of the cerebellum through the large opening in the base of the skull (foramen magnum) into the spinal canal, sometimes causing non-communicating hydrocephalus as a result of obstruction of cerebrospinal fluid outflow. The condition is also called Arnold Chiari malformation.
Type I: The simplest and most common form, is generally considered to be a congenital malformation, although acquired cases are recognized. Commonly goes unnoticed until problems arise in the adolescent or adult years of life. In this condition, the base of the skull and the upper spinal area are not formed properly.
Type II: CM2 is more severe congenital malformation that are apparent at birth and associated with complex defects of the brain and spinal cord. In this condition, part of the back of the brain shifts downward through the bottom of the skull area. Type II Chiari malformations can also be associated with a condition known as hydrocephalus.
Type III: the back of the brain protrudes out of an opening in the back of the skull area.
Headaches, stiffness or pain in the neck or back of the head area, poor feeding and swallowing, decreased strength in the arms, decreased sensation in the arms and legs, developmental delays, weak cry, breathing problems, Tinnitus (ringing in the ears), Vertigo, Nausea, Facial pain, Sleep disorders, Nystagmus (irregular eye movements).
Diagnosis is made through a combination of patient history, neurological examination, and medical imaging. Magnetic resonance imaging (MRI) is the best imaging modality for diagnosis since it visualizes neural tissue such as the cerebellar tonsils and spinal cord as well as bone and other soft tissues.
There are many ways to treat Chiari malformations, but all require surgery. The basic operation is done by removing a small portion of bone at the base of the skull as well as often removing a part of the back of the first and occasionally additional spinal column segments. In addition, the use of endoscopes has allowed for this procedure to be performed through smaller incisions, which helps in the reduction of post-operative pain and speech recovery.