What to Expect the Day of the Procedure
Once the Gamma Knife team has decided that the procedure is appropriate for the patient, he/she is scheduled for treatment. In most cases, the patient arrives at the Comprehensive Cancer Center, Radiation Oncology Department, at 6:30 the morning of the procedure.
The first step is to attach a guiding device (stereotactic frame) to the patient’s head with four screw pins. The patient’s scalp is cleaned with alcohol, and medication is injected to numb the skin before the pins are used. Four pins are inserted, two in the front and two in the back of the head, and the lightweight frame is attached. The patient will feel pressure but should not feel pain when the frame is put on.
Head measurements are recorded to help plan the treatment and the patient has an MRI scan. This scan often takes less time than a routine MRI scan. In some cases CT imaging and angiography are used to plan the treatment.
After the scan is taken, appropriate images are selected and transferred to the Gamma planning computer. Dose planning usually takes one to three hours, depending on the lesion size and location. During the planning process, the patient waits in the Day Hospital and can eat, visit with family, walk around or rest.
After final plans for administering the radiation dose have been made and reviewed by the Gamma Knife team, the patient is moved to the Gamma Knife unit.
The treatment session usually lasts between 30 minutes and three hours, depending on the amount of radiation needed. A number of “trips” in and out of the machine is necessary to accurately deliver radiation to the tumor or AVM.
During treatment the patient does not feel or hear anything unpleasant. Throughout treatment, the patient is observed by closed circuit television and is able to communicate with doctors and nurses via two-way intercom.
After treatment, the guiding device is removed and most people are able to return home shortly after a brief observation period. Some patients stay overnight either before or after the procedure for medical management or additional testing.
The patient can return to normal activities without restrictions the day after the procedure.