Surgery is the most common treatment method for brain tumors. However, some tumors cannot be eliminated because they are too difficult to reach or if the risk of damaging the brain is too high.

You may have surgery to:

- Extract a sample of tissue to confirm the type of the tumor (biopsy)

- Eliminate the tumor entirely

- Eliminate the largest part of the tumor that can be done safely.

- Relieve increased pressure in the brain due to a build-up of fluid.

- Make it possible to give chemotherapy directly to the brain.

• Biopsy

It is usually necessary to perform a biopsy to determine the type of brain cancer a patient has. Part of the tissue is removed to examine the cells under a microscope and check to see if they are cancerous.

Sometimes the biopsy is done during the operation to remove the tumor.

• Craniotomy

An operation called a craniotomy must be performed to remove a brain tumor. During this type of surgery, a section of the bone of the cranium is removed in order to access the cerebral tissue inside. After all or part of the tumor has been removed, the part of the cranium that was moved is put back, and sutures or staples are used to close up the scalp. This is carried out while the patient is under general anesthesia.

Special instruments and a powerful microscope are used to see the brain tissue, making it possible to remove the tumor without damaging the healthy tissue.

If it isn't possible to eliminate all of the tumor, an attempt is made to remove the largest part; this is called partial resection or cytoreduction.

After the operation, all the of the tissue that has been eliminated is sent to the lab to be examined by a pathologist.

• Shunts

If the tumor is blocking the flow of cerebrospinal fluid surrounding the brain, pressure may build up within the brain. In such cases, a shunt is inserted to drain out the excess fluid. A small device called an Ommaya reservoir can also be used.

A shunt is a long, thin tube placed in the brain underneath the skin. It leads to another part of the body, usually the abdomen (peritoneum). This is how excess cerebrospinal fluid is drained into other parts of the body, where it is reabsorbed. The shunt has valves through which the fluid exits the brain but is not allowed back in the opposition direction.

Shunts cannot be seen with the naked eye and are not painful.