Gamma Knife® stereotactic radiosurgery is a form of radiation therapy for brain tumors that can replace other types of surgery in certain cases. WashU Medicine neurosurgeons at Siteman Cancer Center use Gamma Knife to deliver a highly concentrated dose of radiation to the tumor while leaving the surrounding areas intact. The Gamma Knife procedure eliminates tumor cells while keeping healthy cells intact.
Although Gamma Knife is a form of radiation, it is considered a surgical intervention because it can replace surgery. The technology enables physicians to treat brain tumors accurately and safely. Patients with a hard-to-reach tumors or one that was diagnosed as inoperable, may be eligible for this outpatient procedure.
WashU Medicine experts at Siteman Cancer Center were the first in Missouri to use Gamma Knife technology. Since then, we have treated more than 5,000 patients at the WashU Medicine Taylor Family Department of Neurosurgery.
Siteman Cancer Center is a destination for patients seeking Gamma Knife, sometimes traveling nationally for this expertise. The treatment itself requires one to five treatment sessions and is generally done on an outpatient basis. Gamma Knife offers many benefits beyond being a less invasive, surgical alternative. Patients can return home and rehabilitate faster with fewer risks of infection and complications.
Our Siteman care coordinators – oncology-trained nurses who help with scheduling, finding the right specialist, and guidance – can help you through the process.
Call us directly or submit a form, and we will call you back.
Gamma Knife radiosurgery is a treatment option for a variety of malignant and benign brain tumors. The conditions it helps include:
- Arteriovenous malformations (AVMs)
- Brain metastases
- Craniopharyngiomas
- Essential tremor (medically refractory)
- Meningiomas
- Pediatric tumors (selected cases)
- Pineal region tumors
- Pituitary adenomas
- Select gliomas (e.g., small recurrent or residual lesions)
- Trigeminal neuralgia
- Vestibular schwannomas (acoustic neuromas)
- Other select intracranial conditions
This type of treatment is recommended based on a patient’s specific diagnosis, lifestyle, and impact of recovery on the patient’s life.
Why Choose Siteman
WashU Medicine neurosurgeons at Siteman Cancer Center use the Leksell Gamma Knife Icon System, the most sophisticated machine available. This system is unique because it allows for both framed and frameless treatments.
Patients receiving Gamma Knife radiosurgery here can sometimes wear a mesh mask instead of the traditional titanium frame that providers use to keep their heads still during the procedure.
WashU Medicine surgeons at Siteman are experienced in treating benign and malignant brain tumors that are surgically hard-to-reach or inaccessible, pinpointing these brain targets with high accuracy and safety in a well-tolerated outpatient procedure. Gamma Knife radiosurgery is a safe, accurate, and beneficial therapy that delivers precision-guided radiation without requiring incisions or general anesthesia.
Your Second Opinion at Siteman
Siteman wants to be your first choice for cancer care, but that might not always be possible. If you have received a cancer diagnosis, started care somewhere else, or are a physician seeking specialized care for your patient, ask us about a second opinion. You can start the process. To make it easy, our care coordinators guide scheduling for yourself or your patient.
How Gamma Knife Surgery Works
Gamma Knife is a type of radioactive surgery that aims radiation directly on the brain tumor. It delivers a higher dose of radiation than whole-brain radiotherapy, but the dose is broken down into 192 separate beams emitted by the cobalt-60 radiation sources.
Each of these beams on their own is too weak to significantly injure healthy tissue, which is how the technology keeps healthy cells intact. The gamma rays pass safely through the brain until they reach the tumor.
Once it reaches the tumor, all of the beams come together to produce an intense dose of radiation contained within that specific site. The radiation is directed to the tumor like a magnifying glass reflecting the sun. WashU Medicine surgeons use advanced imaging technology to make sure the radiation beams are concentrated on the right spot.
Since this type of procedure is performed on an outpatient basis, patients reap the benefits of surgery without many risks. There are no incisions, so there is a lower risk of infection, bleeding, and complications arising from anesthesia. Local anesthetic is often the only painkiller required.
Frequently Asked Questions About Gamma Knife Surgery
During treatment, the patient’s head is kept perfectly still while radiation is beamed to the tumor. Doctors use either a titanium frame or a mesh mask to hold the patient’s head in place. Each device requires a different preparation process.
The decision to use a frame or a mask depends on the tumor size and whether your treatment will take place during one session or over several sessions. Your diagnosis and treatment plan will determine what is best for you. Frames are well suited for a single Gamma Knife session, while mesh masks work well for multiple treatments. Because the frames attach to your head in a rigid structure and use pins to attach to the skull, it isn’t practical to use if the treatment needs to span over more than one session.
In cases where the treatment needs to be split into multiple sessions, a custom-fitted mask will be used to keep your head still. Masks do not use pins, so surgeons can take them off after your treatment session is over for the day.
After your treatment session is over, you will be monitored for a short period of time before being released to go home. You are not radioactive after treatment, so you can go about your day-to-day activities as you would normally.
Gamma Knife is safer in the short term than traditional neurosurgery, with a much shorter recovery period and a reduced risk of complications.
Some of the key advantages of Gamma Knife treatment include:
- No healthy brain tissues are touched or harmed during treatment.
- There are no incisions, which means you are unlikely to get an infection.
- The process is completed in one to five days and does not require a lengthy stay in the hospital.
- Since the treatment spans over a short period, costs are typically lower than other types of cancer treatment.
- The recovery period is very quick.
- Patients are not radioactive after the treatment and can return to their ordinary routines the following day if they wish.
Most Gamma Knife side effects are not severe and will go away on their own. However, patients may notice the following side effects shortly after the procedure:
- Headache
- Nausea and/or vomiting
- Fatigue
- Redness or irritation where the frame was attached
Contact your doctor or go to the emergency department if you notice or experience any of the following:
- Inflammation or redness at the frame placement sites
- A fever of 101 degrees F or higher
- Seizures
- Changes in vision
- A sudden inability to speak
Because it can take several weeks or months for radiation to take full effect in your brain, some side effects may develop over time. These include:
- Headaches
- Brain swelling around the tumor
Brain swelling sounds alarming, but in these cases, swelling is not as dangerous or urgent because it develops more gradually. Medications such as corticosteroids can reduce or prevent swelling.
Be sure to speak with your doctor about any concerns you may have. Our nursing staff is also extremely knowledgeable and welcomes questions from patients and family members. We want you to be able to participate fully in your care and to know how best to handle your recovery at home.