Gamma Knife® surgery is a form of stereotactic radiosurgery, which is highly precise radiation therapy. Instead of making surgical incisions to access the treatment area, the radiology team focuses more than 200 radiation beams on the surgical target. Doctors use Gamma Knife surgery to treat brain tumors, vascular malformations in the brain, and other brain abnormalities. Exploring other treatment options first Depending on your specific condition, your doctor may recommend less invasive treatments first. This may include standard radiation therapy, chemotherapy, and other medications. Ask your doctor about all treatment options and consider getting a second opinion before deciding on Gamma Knife surgery. When to consider Gamma Knife surgery You may want to consider Gamma Knife surgery if you have a brain condition requiring surgery to repair or remove it. Your doctor may decide you are a good candidate for Gamma Knife surgery if: The tumor or vascular malformation is small. The tumor or vascular malformation is difficult to reach using traditional surgery. The tumor or vascular malformation is located very close to critical brain structures, making traditional surgery risky. Traditional surgery has not worked. Traditional surgery is too risky due to age or other medical conditions. You have a metastatic brain tumor (a tumor derived from cancer elsewhere in your body, such as the lung) and are already receiving treatment for the main cancer. You have a metastatic brain tumor that came back after radiation therapy. You may also choose Gamma Knife surgery based on your personal preference to avoid surgery. When Gamma Knife surgery may not be right for you You may not be a good candidate if: Your brain condition is causing disabling symptoms requiring immediate relief. The effects of Gamma Knife surgery can take several weeks. Your tumor or malformation is larger than 4 to 5 cm. Your condition does not allow for the use of the head frame. A head frame for use during a CT scan or MRI is necessary to locate and focus the treatment at the correct spot. Tumors below the skull base may be out of range for the head frame. Infants and toddlers whose skull bones are not fully fused are also unable to use the head frame. Frameless radiosurgery may be an option. What to expect with Gamma Knife surgery Highly trained neurosurgeons, radiologists, and possibly other types of doctors who specialize in your specific condition are part of a Gamma Knife treatment team. The neurosurgeon will most likely lead the team. Other team members include nurses and healthcare professionals who prepare you for treatment. The first part involves the stereotactic head frame and imaging test. Your team will use a local anesthetic to numb the area where they attach the head frame with pins. You may also receive a sedative to help you relax. Children may have general anesthesia so they sleep through the entire procedure. An MRI or CT scan creates a detailed image of the treatment area. The second part involves the radiation treatment. Your doctors use a sophisticated computer program to calculate the exact amount and pattern of gamma radiation beams to deliver. This can take 1 to 2 hours. Finally, a team member places a special helmet over your head frame and positions you on a table in the Gamma Knife unit. From here, the table slides into the machine and you receive radiation through the helmet. The table slides back out and you move to a recovery room. After the procedure, you may have minor bleeding from the pins. The results of Gamma Knife surgery take place gradually. Tumors and vascular malformations shrink over several months. It’s also possible you will need more than one radiation treatment. Talk with your doctor to find out what you can expect for your specific condition.