Cranio-cervical decompression for chiari malformation

What is an chiari malformation?

An chiari malformation is when the bottom part of the brain is forced through an opening in the base of the skull into the space where the spinal cord usually sits.

What are the symptoms of chiari malformation?

This can cause compression in the brain stem and disrupt of the flow of cerebrospinal fluid at the top of the spinal canal. This can cause a number of symptoms including:

• pain and tingling in arms and legs
• dizziness
• feeling sick
• balance problems
• visual disturbances
• problems swallowing
• pressure headaches which worsen when straining, laughing or coughing

Some children with chiari malformations have very few symptoms and may not need treatment. Any decision to go ahead with surgery will be discussed with your consultant and will take into account the severity of the symptoms alongside the risks of surgery.

What is a syrinx?

Some children with a chiari malformation develop a condition called syringomyelia. Syringomyelia is where a fluid-filled cyst (syrinx) develops within your spinal cord. This is called a syrinx and will be treated depending on symptoms.

What is a cranio-cervical decompression?

A cranio-cervical decompression is an operation at the top of your child’s neck to lift the area at the bottom of the brain and make extra room around the spinal cord. This will relieve the pressure caused by compression around their spinal cord.

What does a cranio-cervical decompression involve?

A cranio-cervical decompression is done under general anaesthetic. The surgeon will open the skin and muscle around the area and adjust the position of the cerebellar tonsils and shape the skull to create more room for the brain and spinal cord.

The wound will then be closed and a head bandage applied. It may be necessary to shave a small piece of your child’s hair at the back of the head and will leave a wound size of 5 to 10cm.

What are the potential risks and side effects of the surgery?

As with any surgery there are risks involved and these will be fully discussed with you before the procedure. These risks include:

Pain

Regular pain relief will be prescribed to help with general post-operative pain. The physiotherapists will be involved in the recovery period to encourage your child’s movement to prevent stiffness and to maintain full range of movement.

Feeling and being sick

Because of the change of pressure in the brain, children can sometimes feel and be sick after the operation. We can give your child intravenous (IV) fluids to stop them from being sick, and keep them hydrated.

Infection

As with any wound site, there is a small risk of infection. Making sure the wound is kept clean and dry will reduce the risk of this.

Bleeding

Surgery can disrupt the blood vessels and may cause some bleeding.

Failure of surgery

On very rare occasions, the surgery may not be as effective as planned and the chiari malformation may remain (either partially or fully). If this happens, surgery may need to be repeated in the future if symptoms persist.

Hydrocephalus

The flow of cerebrospinal fluid may be disrupted during the procedure, and lead to a build up of fluid within the ventricles (fluid filled spaces) in the brain, called hydrocephalus. This may be temporary and fix itself, but it might need further treatment which will be discussed with you at the time.

Leak of cerebrospinal fluid

Due to the opening of the skull, there is a chance that cerebrospinal fluid may leak from the wound site. This will either be a visible leak onto the skin or a internal leak under the skin creating a pocket of fluid. In these cases the surgeons will discuss the treatment options with you including re-stitching the wound, applying a pressure dressing and treating hydrocephalus.

What will happen after the surgery?

After the surgery your child will need to spend 24 to 48 hours on the high dependency unit (HDU) or to the neurosciences ward to make sure your child recovers well.

A head bandage will be applied during the surgery which will need to stay on for a few days. Pain relief will be given to your child regularly and will be encouraged to move as much as they can. The ward physiotherapists and occupational therapists will visit regularly to help with this. You child may also feel sick but medication can be given to help with this.

What will happen when we go home?

The aim of surgery is to get your child back to normal life as possible. Some children may have symptoms that carry on when after treatment of the chiari malformation. A follow-up appointment will be arranged for a review after the initial post-operative period has settled.