Chiari Malformation Repair Brain Surgery

Chiari malformations are structural defects that can occur in the cerebellum and spinal cord. These rare abnormalities cause the brain to protrude into the spinal space at the back of the skull.

Most of the time, Chiari malformations are present at birth. These defects can occur much later in life. However, this is not very common. It is estimated that approximately one out of every 100,000 children are born with Chiari malformations.

Candidates for a Chiari Malformation Repair

Individuals may be candidates for Chiari decompression surgery when the malformation obstructs the flow of cerebrospinal fluid, or CSF, in the back of the neck and spine, as this can cause symptoms of headaches, neck pain, ringing in the ears, balance problems, and vomiting, However, Chiari malformations may cause no symptoms at all. Chiari malformations are usually confirmed through a cine MRI.

Even though Chiari is typically present at birth, patients generally do not experience symptoms until they reach adulthood. Surgery is not necessary in every case. People who don't experience symptoms may have their condition monitored by their doctor. Those with mild neck pain or headache because of Chiari can be treated with prescription medications.

When the condition is severe and interferes with the activities of daily living, a doctor may recommend surgery.

What is Chiari Malformation Repair?

Chiari decompression surgery is a procedure that is used to relieve pressure on the spinal cord and cerebellum. Chiari malformations can cause changes to the spinal cord and brain if not treated. Decompression surgery can help relieve symptoms and stop the progression of changes.

Chiari decompression surgery is performed in a hospital with the patient placed under general anesthesia. During the surgery, a surgeon will remove a tiny portion of the skull. In some cases, they may need to remove a small part of the spinal cord, as well. This widens the space available and relieves compression on the brainstem and tonsils.

The most common type of surgery for Chiari malformations is a posterior fossa decompression. During this surgery, a specialized surgeon will relieve compression on the brain and spinal cord by removing a small section of the skull at the back of the head. In rare cases, the removal of a vertebra may be required using a procedure called a spinal laminectomy.

Once asleep, the patient's hair will be shaved to clear the scalp for the incision. The patient’s head is placed in a device that holds the head still. This helps prevent the head from moving during surgery.

In some cases, bone removal alone may restore Cerebrospinal Fluid (CSF) flow. If bone removal alone doesn’t relieve compression, the surgeon will make a small incision at the back of the head. They will then lift the dura, which is the material that covers the brain, in order to place a piece of scalp tissue called a dural patch, outside the skull. The dural patch is used to enlarge the dura and the space around the tonsils.

If the herniation is large, the surgeon may shrink the damaged tonsils with electrocautery.

Results of A Chiari Malformation Repair Procedure

Results of the procedure vary according to the severity of the patient's Chiari malformation, as well as the extent of existing nerve and brain injury. Between 85 and 95 percent of patients report major relief of symptoms after the surgery.

Some patients do have residual symptoms of the condition and if the existing injury to the spinal cord was permanent before the surgery, it cannot be reversed.

Symptoms of Chiari such as exertional headaches and pain in the neck tend to respond well to the procedure, as do symptoms associated with the brainstem such as numbness or pain in the face, tinnitus, problems with swallowing, dizziness and various eye problems.

What are the risks of Chiari Malformation Repair?

Risks with this procedure are uncommon. These can include bleeding around or in the surgical site as well as infection. Nerve damage, paralysis, stroke, CSF leakage, brain sag and hydrocephalus are also possibilities. Moreover, a bulge containing CSF may develop beneath the skin at the site of the incision in a condition called pseudomeningocele.