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What is the Gamma Knife?
The Gamma Knife is not actually a knife at all. Rather, it is an instrument that uses targeted radiation to perform brain surgery. The Gamma Knife allows the doctor to focus 201 beams of radiation just on the area being treated. Alone, each beam is too weak to cause any damage to the normal brain tissue. The Gamma Knife is extremely precise. It uses 3-D planning to shape the radiation dose to the size and shape of the affected area. The Gamma Knife is only used on the brain. It is used to treat:
Vascular Disorders
In most cases, only one Gamma Knife treatment session is needed. The treatment begins early in the morning and lasts the most of the day. It involves 4 phases:
An overnight hospital stay is required.
The Gamma Knife Team
The Gamma Knife team consists of a neurosurgeon, radiation oncologist, radiation
physicist and registered nurse. Together the team provides care tailored
to your specific needs.
Before Surgery
Certain blood tests must be done prior to the Gamma Knife treatment:
If you have had these tests within 30 days of your Gamma Knife appointment, there is no need to repeat these tests. Please arrange to have the blood test results sent to the Gamma Knife Center:
Gamma Knife Center
251 E. Huron Galter Pavilion, L-178
Chicago, Il 60611
Fax: (312) 926-6845
The Gamma Knife nurse meets with you or calls you at home. Talk to the nurse about any allergies (including iodine or x-ray contrast) and your current medications. Check which medicines may be taken on the day of "surgery." The nurse will also review what to expect on the day of treatment including:
The nurse also:
It is helpful to review the Northwestern's Angiogram/ Ateriogram brochure (provided by the Gamma Knife nurse). This explains what to expect during and the care needed after the angiogram.
Night Before Surgery
Do not have anything to eat or drink after midnight the night before your
procedure. Any needed medicine may be taken with sips of water.
Day of Surgery
On your scheduled day of surgery, plan to arrive at 7 am, unless instructed
otherwise.
As directed, take needed medicines with sips of water. Wear comfortable clothing. Your own slacks may be worn for the treatment if they do not have metal in them.
Do not wear any makeup.
Please come to the Galter Pavilion, 201 East Huron. The parking garage is across the street from the hospital between Huron and Superior on St. Clair Street. Be sure to bring your parking ticket into the hospital for validation. Take the elevators to the 4th floor. It is important that you:
The nurse from the Gamma Knife Department will meet you to escort you to the Radiology holding area. Only two family members may accompany you to the Radiology holding area because of limited space.
Head Frame Placement & Imaging
When you arrive in the Radiology holding area, you are asked to change into
a hospital gown.
The nurse reviews the procedure with you, answers any questions and shows you the Gamma Knife head frame in detail. You are asked to sign consent forms. An IV (into the vein) line is inserted. The IV is used to give contrast (dye) and fluids during the surgery. The doctor reviews your medical history and does a short physical exam. The nurse checks your blood pressure and pulse.
The neurosurgeon then places the Gamma Knife frame on your head. The frame has special "markers" on its surface. These markers are used to map the exact location of your Gamma Knife surgery.
The frame is held firmly in place by four pins: two on the forehead and two on the back of the head. No hair is shaved from your head and no incisions are made. Your pin sites are cleaned with alcohol and numbing medicine is injected into the area. This assures comfort during the frame placement. You will feel pressure as the pins are put in place. This is normal and the pressure does subside. The frame remains on your head until after your surgery. When the head frame is in place, a MRI scan is done. A CT scan may be done instead, if you have metal in your body, such as a pacemaker or ear implants.
Next, the angiogram is done in Interventional Radiology. Once completed, the nurse takes you per cart to the Gamma Knife Center in the Radiation Oncology Department. It is important that you lay flat for the next 6 to 8 hours after your angiogram. During this time the nurse checks the puncture site along with your blood pressure and pulse.
Planning Phase
When you arrive in the Gamma Knife Center, the planning phase begins. The
Gamma Knife team uses a computer to plan your specific radiation treatment.
The planning phase may take an hour or more, depending on the size and shape
of the area being treated. During this time, you will be made comfortable
in the Gamma Knife Center and your family is welcome to wait with you.
Surgery
After the planning phase, the treatment or surgery phase starts. The nurse
helps you lay on a special bed. The team positions your head to direct the
radiation to the targeted area of your brain. When your head is in the correct
position, the team makes you as comfortable as possible. Then, because of
the radiation, the team must leave the room. During the Gamma Knife treatment:
Surgery time varies based upon your specific treatment plan.
After Surgery
When your treatment is over, your doctor removes the head frame. Antibiotic
gauze and band-aids are applied to each pin site. Some patients may have
slight bleeding at the pin sites. Applying pressure almost always stops
the bleeding.
You are then taken to your hospital room on the Neurosurgery floor. You may have a mild headache from the frame removal. Your nurse can give you medicine for the pain. You may also have swelling above your eyes. This is caused by the numbing medicine used during the frame placement. The swelling lasts only a short time. Your nurse will apply ice packs to your forehead to help prevent the swelling. It is important to continue to use the ice packs after you go home.
During your hospital stay,
Follow-Up Care
Before you leave the hospital, specific discharge instructions are given
based on your diagnosis. This will also include guidelines for care after
an angiogram. The full effects of Gamma Knife surgery do not happen right
away, which makes follow up care very important. This care includes doctor
visits and imaging studies such as MRI or CT scans. Please call your Gamma
Knife neurosurgeon's office at (312) 695-8143 to make your follow up appointments
as instructed.
When to Call the Doctor A small number of people have side effects from Gamma Knife surgery. Call you doctor if you have:
There is some risk with every surgery. The risk varies with each person and the problem being treated. The risks of Gamma Knife surgery are low compared with traditional brain surgery. Most side effects are temporary. Your surgeon will discuss the benefits and risks involved in your surgery with you. Please ask your doctor if you have any questions or concerns.
We Welcome Your Questions
We are happy to talk with you and answer your questions about Gamma Knife
surgery. The Gamma Knife nurses are on hand to talk with you on weekdays
between 8: 30 a. m. and 4: 30 p. m. (Central Standard Time). Please call
us at (312) 926-5070.
Looking for a doctor? Request an appointment online.
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