Unlike other radiosurgery systems - such as the Gamma Knife - the CyberKnife does not require invasive head frames to prevent movement during treatment. The CyberKnife tracks the tumor's position during treatment and automatically adjusts the treatment delivery.
In the set-up stage, the radiation therapist will create a soft mesh mask that is custom-fitted to the patient’s face. This comfortable and non-invasive mask helps the patient keep his or her head and neck still during treatment. While wearing the mask, a CT scan will be performed. The CT data then will be used by the CyberKnife team to determine the exact size, shape and location of the tumor.
An MRI, PET scan or angiogram also may be necessary to fully visualize the tumor and nearby anatomy. Once the imaging is done, the face mask will be removed and stored until the CyberKnife treatment begins. Then a medical physicist and the patient’s doctor use the data to custom-design the patient’s treatment plan. The patient does not need to be present at this time.
During the CyberKnife treatment planning phase, the CT, MRI and/or PET scan data will be downloaded into the CyberKnife's treatment planning software. The medical team will determine the size of the area that must be targeted by radiation and the radiation dose. They also will identify critical structures where radiation should be minimized. Using this information, the CyberKnife calculates the optimal radiation delivery plan to treat the tumor. The treatment plan will take full advantage of the CyberKnife’s extreme maneuverability, allowing for a safer and more accurate treatment.
After the brain cancer treatment plan is developed, the patient will return to the CyberKnife Center for treatment. The doctors may choose to deliver the treatment in one session, or stage it over several days. Typically, brain cancer treatments are completed within five days. For most patients, the CyberKnife treatment is a completely pain-free experience. Patients dress comfortably in their own clothes and, depending on the treatment center, they may be allowed to bring music to listen to during the treatment. Patients also may want to bring something to read while they wait, and have a friend or family member with them to provide support before and after treatment.
When it is time for treatment, the patient lies on the table while their custom-fitted face mask is secured into place. The CyberKnife’s computer-controlled robot will move around the patient’s body to the various locations from which it will deliver radiation to the tumor. Nothing will be required of the patient during the treatment, except to relax and lie as still as possible.
For more information about CyberKnife, call 253-403-6399.