The Brain Centre

What is Gamma Knife Radiosurgery?

There is no actual knife in Gamma Knife. It provides a completely non-invasive procedure, without any blood. The radiosurgical treatment delivers a dose of radiation to the target with surgical precision. Common diseases treated with Gamma Knife radiosurgery are brain cancer and other brain abnormalities such as AV malformations. It is the most accepted and widely used radiosurgery treatment in the world. Over 500.000 patients have been treated with Gamma Knife surgery and it is the only Radiation Therapy System cleared by the FDA for irradiating brain metasteses.

For more information, please go to the Gamma Knife page and Treatment.

Is it effective?

Over 500,000 patients worldwide have chosen Gamma Knife Radiosurgery for treatment of benign tumors such as acoustic neuromas, meningiomas, pituitary adenomas, pineal tumors; malignant tumors like metastatic tumors, astrocytomas and glioblastomas. The Gamma Knife has also been used to eradicate arteriovenous malformations (AVM) and treatment protocols are under investigation for certain functional disorders such as chronic pain, trigeminal neuralgia, and Parkinson’s disease.
Patients may be eligible for Gamma Knife Radiosurgery even if they have previously had open brain surgery, radiation therapy, chemotherapy, or in the case of AVM, embolization procedure. Results have proven to be superior or comparable to conventional neurosurgery, depending on the specific condition treated.

Is it safe?

Gamma Knife Radiosurgery is unique because no surgical incision is performed to “expose” the lesion. Consequently, the risk of surgical complication is greatly reduced. Patients are routinely administered a mild sedative, eliminating the side effects of general anesthesia. Patients are usually able to leave the treatment centre the same day and resume their normal everyday activities.
Gamma Knife Radiosurgery uses radiation beams and these beams causes injury to the DNA structure of the treated tissues, which is why cells die when exposed to radiation, but it does not make them radioactive.

What can I expect after treatment and how quickly will I see results?

When the treatment session is finished, the head frame will be removed. Sometimes there is a little bleeding from where the pins were attached to the head. Gauze and pressure will be applied to stop the bleeding and keep the area clean. A small patch is placed over the pin locations. It is recommended that the patient take it easy over the next 12-24 hours. Normal activities can be resumed within a few days, depending on the medical condition treated.
The effects of Gamma Knife Radiosurgery occur over a period of time that can range from days to several years, depending on the type of medical condition treated. Some abnormalities dissolve gradually, eventually disappearing. Others simply exhibit no further growth. The effectiveness of the treatment is monitored by MRI scans at regular intervals. The goal of radiosurgery is tumor control, which is defined as stable tumor size or tumor shrinkage.

What are the patient benefits?

Cost studies have shown Gamma Knife Radiosurgery to be less expensive than conventional neurosurgery because it eliminates lengthy post-surgical hospital stays, expensive medication and sometimes months of rehabilitation. Importantly, there are virtually no post-surgical disability and convalescent costs with this procedure.

When can I return to my normal activities?

Within a few days. The only restrictions you will have are the same you had prior to your treatment.

Is the treatment painful?

No, some patients feel a slight discomfort from the local anesthetic used prior to frame placement, but most patients handle it very well. Apart from that, the actual treatment inside the Gamma Knife is completely painless and the patient does not see or feel the radiation at all.

What are the side effects of the Gamma Knife?

Complications are infrequent or rare compared to conventional surgery. Early complications may include headache, numbness at the site of the pin placement and tiredness. Some tumors may swell up before they shrink but that is quite unusual.

What are the advantages of Gamma Knife Radiosurgery?

Gamma Knife surgery has many advantages compared to traditional surgery and other types of radiation treatment. It is a dedicated neurosurgical tool designed specifically to treat brain disorders, thereby providing greater accuracy than other radiosurgery systems.
Gamma Knife is bloodless and painless, allowing the patient to return to normal activities within days, with essentially no mortality after treatment of over 500.000 patients worldwide. It can be used in many inoperable cases, replacing conventional brain surgery, but also in conjunction with microsurgery, serving as a complement.
Gamma Knife is the Gold Standard of radiosurgery systems, as documented in more than 2000 peer-reviewed medical articles, which is more than all other systems combined.

Will I lose any hair?

No, you do not need to shave your hair and your hair will never be lost over the entire scalp as may happen with conventional whole brain radiation. In some cases when the target treated is very close to the base of the skull, you may lose a patch of hair.However, it should grow back. Since each beam of radiation is not sufficient to cause any permanent damage to the skin, it is unlikely that hair loss occurs.