about | Maps & Directions | contact | admissions | faculty | alumni & development | library | Tech Support Center | dean's office | Policies & Procedures

department of radiation oncology

Information for Patients


Preparing for Gamma Knife® Surgery

The entire procedure is usually completed the same day you arrive. You'll start by meeting with your doctor, who will discuss the details of the surgery and answer any questions. You may be given medication to help you relax.



The Stereotactic Head Frame

You will then be fitted with a lightweight metal frame which fits around your head and is attached at four pin sites. Local anesthesia will numb these sites while the frame is being fitted. Most patients report that they experience little or no discomfort. The frame allows your doctor to accurately pinpoint the target to be treated in your brain. It also prevents your head from moving during imaging and treatment procedures.



After your head frame is in place, you will have one or more advanced imaging tests—such as an MRI or a CT scan—to precisely identify the size, shape and location of your tumor, lesion or abnormality. If your physician is treating a blood vessel abnormality, an angiogram may also be required. (An angiogram involves the injection of a dye into your bloodstream so that the blood vessels and arteries in your brain are clearly shown).

Once your images have been taken, you can relax while your physician develops a very precise, accurate treatment plan that is customized for each patient. This process may take up to several hours. The doctor, often together with another specialist on the team, creates your specific plan in a specially designed computer and calculates how the treatment should be peformed.



When your treatment plan is completed, the actual surgery can begin. You will be helped onto a couch and your head frame will be attached to a positioning device called the helmet. When the procedure begins, the couch will slide into the dome section of the unit. You will be awake during the surgery and will be able to communicate with your doctor or nurse through an audio and video connection. The treatment is silent and totally painless, and often you are able to listen to music.

The medical team monitors the procedure at all times. The treatment will last anywhere from a few mintues to over an hour, depending on the size and shape of the target.



When your treatment is complete, the head frame will be removed. If you had an angiogram, which involves an IV, you might be required to remain in a reclining position for several more hours so that the doctors can continue to monitor you. Some patient experience a mild headache or minor swelling where the head frame was attached, but most report no discomfort following surgery.

Your doctor will tell you whether or not you should remain in the hospital overnight for observation or if you can go home immediately. Either way, you should be able to return to your normal routine within another day or two.

Side Effects

Side effects of radiation therapy depend on the type of radiation, the location and size of the target, and the radiation dose. There may be hair loss, skin irritation, hearing problems, nausea or vomiting, neurologic effects which may include memory or speech problems, and loss of appetite. The most common side effect is fatigue.


The effects of your treatment will occur over time. Radation treatments are designed to stop the growth of tumors or lesions, which means that the effect will be seen over a period of weeks or months. Your doctor will stay in contact with you to assess your progress, which may include follow-up MRI, CTs or angiography images.