Posterior Fossa Decompression for Chiari Malformation

What is Chiari malformation?

Chiari malformation arises when brain tissue migrates to the spinal canal, which is more likely to occur due to a smaller or misshapen skull. As a result, this increases pressure on the brain.

There are different types of Chiari malformation, but the following 2 are the most common:

• Chiari malformation type 1: Symptoms of this form of Chiari malformation develop during late childhood and adulthood. Headaches are the most common sign often associated with Chiari malformation. Headaches are accompanied by neck pain, issues with balance, a tingling sensation in the hands and feet, difficulty swallowing and voice hoarseness.
• Chiari malformation type 2: With this type of Chiari malformation, a larger amount of tissue infiltrates the spinal canal. It’s almost always co-occurs with a myelomeningocele, a condition whereby the spinal canal and backbone fail to close adequately before birth. Typical signs of Chiari malformation type 2 include difficulty swallowing, arm weakness and changes to the breathing pattern.

How do you treat Chiari malformation?

Treatment is largely dependent on your condition. For example, if the condition appears asymptomatic, your doctor will instead continuously monitor your symptoms, utilising routine exams and MRI scans.

However, if Chiari malformation results in symptoms, your doctor will advise surgery to alleviate discomfort. Posterior fossa decompression is a surgical procedure to alleviate pressure by preparing for the resection of a small fragment of bone from the back part of the skull in order to create enough room for the brain this may sometimes be combined with a duraplasty which may increase the efficacy but also increases the risk of developing a CSF leak.