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Surgical Treatment of Brain Arteriovenous Malformations (AVM)


Why Treat My AVM?

An AVM is composed of an abnormal collection of blood vessels with weakened walls. These abnormal blood vessels have a tendency to bleed. Treatment is recommended to protect against bleeding from the AVM in the future, which may lead, to stroke, permanent disability or even death. About 4 in 100 people with an AVM will have a bleed (haemorrhage) every year. The chances of dying from a bleed is about 10% while the risk of a disability may be as high as 40% with each bleed. The collective risk over a lifetime may be extremely high, especially in a young person. This is why it is very important to treat an AVM.


What Does Surgical Treatment Involve?

Surgery has been the traditional method of treating an AVM. The procedure is carried out by a Neurosurgeon who will excise the AVM under general anaesthesia in the operating room. The AVM is adjacent to normal brain but does not contain brain cells within it allowing removal by the surgeon.


How Does It Work?

Once an AVM is completely taken out surgically, the patient is cured. An AVM does not grow back. The risk of bleeding is thus eliminated immediately after the surgery completely removes the AVM.



Which AVMs Can Be Treated With Surgery?

Not all AVMs can be treated with surgery. Your surgeon will have ordered tests like the CT scan or MRI, which tell him the size, and exactly where in the brain the AVM is located. The surgeons will then decide if it is safe to remove without serious complications.



The Procedure

The surgical procedure is performed by a highly skilled team of Brain Surgeons, Anaesthetists and Nurses in the operating room.

Before Surgery
Before the surgery, you will be admitted to the hospital. Routine blood and urine tests and perhaps a chest x-ray and an ECG will have been done as an outpatient to make sure that you are fit for surgery. After midnight, no food or drink is allowed. In some cases, your surgeon might recommend a pre-operative embolization to be performed on the day prior to your scheduled surgery.

The Day of the Procedure
You will be taken to the operating room 30 minutes before the operation. After the Anaesthetists put you to sleep, the procedure begins. An area of your head may be shaved. The surgeons will then perform a procedure that is called a craniotomy, which means an opening in the skull. The AVM is then carefully cut out from the surrounding brain. The surgery may take several hours. How long depends on the difficulty encountered by the surgeons. At the end of the surgery, a head dressing will be applied to your head and you will be taken to the Neurosurgical Intensive Care Unit where you will be observed closely.

Recuperation in Hospital
You will be moved back to your room in 1-2 days. If all goes well, you will be discharged home within a week after surgery. A repeat angiogram will be performed to ensure the AVM has been completely removed.

Convalescence at Home
A period of rest will be required at home. Sometime a course of physiotherapy is required.



What Are the Side Effects?

The side effects vary with the location of the AVM in the brain. Your doctor will discuss the risks of serious complications association with the surgical removal of your AVM with you prior to surgery. Possible side effects include stroke-like symptoms such as weakness in one arm or leg, numbness, tingling, speech disturbance, visual problems or even paralysis.
The doctor will usually prescribe a course of medication to prevent seizures caused by irritation of the brain by the surgery.



What Are the Chances of Completely Curing my AVM with Surgery?

The chances of completely curing an AVM using surgical treatment is very high. When completely removed, the AVM will not recur.


What are the advantages of Surgery?

  • Complete removal of the AVM gives immediate complete protection against bleeding.
  • Only one surgical procedure is usually required.


What are the disadvantages of Surgery?

  • General risks of surgery would include infection and the possible need for a blood transfusion.
  • Surgical treatment is only possible if the AVM is located in an area that is easily accessible to the surgeon.
  • A longer hospital stay than any of the other treatments.
  • A change of stroke or permanent deficit occurring as a result of the surgical treatment depending on the location of the AVM in your brain.