What Is Stereotactic Radiosurgery?

Medically Reviewed by Laura J. Martin, MD on June 15, 2020

If your doctor suggests you get stereotactic radiosurgery, it doesn't mean you'll have a traditional operation. Instead, a specialist called a radiologist aims radiation at growths or lesions in your body, including cancer, to reduce their size or destroy them.

Doctors typically do it in one session, though in some cases you may need to come back for more, usually no more than five.

What Does Stereotactic Radiosurgery Treat?

Most often doctors use stereotactic radiosurgery to treat problems around the brain or spinal cord. These could include:

  • Cancer
  • Epilepsy
  • Misfiring nerves (neuralgia)
  • Tangled blood vessels (arteriovenous malformations)

What to Expect Before Stereotactic Radiosurgery

Sometimes your medical team will analyze your tumors from imaging (CT scan, MRI, X-rays) and other tests in the weeks or days before the procedure. This helps them figure out the amount of radiation and at what angle to direct it. Doctors don't want to use more radiation than necessary so they can protect healthy cells. They might do all or part of this analysis on the day of the procedure.

Your doctor may ask you not to eat or drink anything after dinner the night before you have stereotactic surgery. You also may need to adjust doses or hold off taking some medications, like insulin or oral medicine for diabetes. Tell your doctor about all the medications you take, including vitamins or supplements.

Also, tell your doctor about medical devices inside your body, which could also affect treatment. These might include:

What to Expect During Stereotactic Radiosurgery

The procedure is "outpatient," which means you don't need to stay overnight in a hospital. But you'll spend several hours at the medical facility where it happens, and you may need someone to help you get home.

There are four basic steps for stereotactic radiosurgery:

Head frame placement. For the radiation to hit the target exactly, your head has to stay very still. To do that, your medical team will first give you a shot of medicine called an anesthetic to numb the skin over your skull and forehead. Then they attach a box-shaped frame to your head. In some cases, your team may make a special plastic mask for you to use instead of the frame.

Imaging. Your doctor will put a special dye into your blood. You'll then get an MRI or CT scan to help figure out where to aim the radiation.

Dose planning. After imaging from the CT scan or MRI, your medical team typically spends an hour or two analyzing the pictures. They may do some or all of this analysis in the days before the procedure. Special computer software helps determine the dose.

Radiation delivery. You will lie down on the radiation delivery machine. There are two main types: gamma knife or linear accelerator. A third type, called proton beam therapy, is available only at several research centers. Your head will be fixed in place with the frame or mask, and in some cases you will wear a helmet with a microphone so that you can talk to the doctor.

Your medical team will help you get comfortable with blankets and pillows. You shouldn't feel any pain, though you might see white flashes as the doctor delivers the radiation to certain parts of your brain. The table often moves to get you in just the right position for the radiation, and with the linear accelerator, you could see a robotic arm that moves around you. The treatment typically lasts from less than an hour to 4 hours.

What to Expect After Stereotactic Radiosurgery

Your doctor will remove the frame and put a bandage on the spots where it was attached. You might have some pain and swelling in the area, but it isn't typically serious, and most people return to normal activities the next day.

You may have side effects from the radiation. It depends on the type of treatment and where the doctor directs it. The side effects usually go away within a few days or weeks and might include problems like:

Talk to your doctor about the risk of more serious complications and long-term side effects for stereotactic radiosurgery, which though possible, are fairly rare.

WebMD Medical Reference



American Association of Neurological Surgeons: "Stereotactic Radiosurgery."

Johns Hopkins Medicine: "Stereotactic Radiosurgery." "Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiotherapy (SBRT)."

UW Health: "Stereotactic Radiosurgery: A Patient Guide."

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