Stereotactic Radiosurgery

Stereotactic radiosurgery is a form of radiation therapy. It delivers high doses of radiation in tiny beams of energy that target tumors and brain abnormalities while avoiding healthy tissue. Healthcare providers use this to treat cancerous and noncancerous brain tumors, brain abnormalities and cancerous tumors in your lungs, liver or pancreas.


What is stereotactic radiosurgery?

Stereotactic radiosurgery is a form of external beam radiation therapy (EBRT). Despite its name, stereotactic radiosurgery doesn’t involve incisions. Instead, this radiation therapy uses machines that pinpoint issues with many tiny beams of high-dose radiation.

Radiation oncologists and neurosurgeons use stereotactic radiosurgery to treat certain brain conditions — including brain tumors — and small tumors in other parts of your body. Stereotactic radiosurgery lets healthcare providers target problem areas while minimizing potential damage to healthy tissue.

Types of stereotactic radiosurgery

All types of stereotactic radiosurgery target tumors and abnormalities with many tiny beams of radiation. On their own, the beams don’t damage healthy tissue. When the tiny beams come together, they deliver a powerful dose of radiation.

Stereotactic radiosurgery types include:

  • Gamma Knife®: This procedure treats brain tumors and brain issues.
  • Stereotactic body radiation therapy (SBRT): Providers use this treatment for small cancerous tumors in your lungs, liver, prostate and pancreas.
  • Proton therapy: This treatment, also known as particle beam radiation therapy, works by delivering concentrated streams of high-energy particles into your body. Providers use it to treat many central nervous system cancers and tumors in other areas of your body.
  • Linear accelerator (LINAC): This machine delivers image-guided radiation therapy (IGRT) and intensity-modulated radiation therapy (IMRT).

What conditions are treated with stereotactic radiosurgery?

Radiation oncologists and neurosurgeons use stereotactic radiosurgery for small cancerous or benign (not cancerous) tumors in your brain and certain areas of your body. Neurosurgeons may use it to treat brain abnormalities.

Cancerous brain tumors

Stereotactic radiosurgery treats tumors by damaging the DNA in cancerous cells so that tumors stop growing, including:

Benign brain tumors

Like cancerous brain tumors, stereotactic radiosurgery keeps benign tumors from growing by damaging tumor cells’ DNA. Radiation oncologists use it to treat:

Brain abnormalities

Stereotactic radiosurgery targets brain abnormalities or the area of your brain that shows symptoms. Examples include arteriovenous malformation (AVM) and tremors associated with neurological disorders, like Parkinson’s disease or trigeminal neuralgia.

Other cancerous tumors

Stereotactic radiosurgery also treats other kinds of cancerous tumors, like:


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Procedure Details

What happens before this procedure?

All types of stereotactic radiosurgery involve extensive planning, but the exact process may vary depending on the treatment type. In general, your team will:

  • Do a medical review: They’ll confirm this treatment is appropriate in your case. Your team will ask if you have any implanted devices for heart or cancer treatment, allergies to intravenous contrast material or iodine and if you have claustrophobia.
  • Explain the process: There’s a lot that goes into this treatment. Don’t hesitate to ask questions, particularly if anything about treatment makes you feel anxious.
  • Do imaging tests: Tests may include computed tomography (CT) or magnetic resonance imaging (MRI) scans to pinpoint tumor location. People with brain tumors or brain issues will have brain MRIs.
  • Do treatment planning: This may include simulating treatment, which is like doing a practice run before the actual treatment.
  • Establish dosage: Your team will determine if you’ll get a single high dose of radiation or smaller doses over several treatment sessions. They may call this fractionated treatment or stereotactic radiotherapy.
  • Prepare immobilization devices: You’ll need to stay very still during stereotactic radiosurgery so that radiation hits the tumor and not healthy tissue. Immobilization devices help with that. For example, if you’re having brain cancer treatment, your team will fit you with a head frame.

What happens during stereotactic radiosurgery?

The specific process depends on the type of stereotactic radiosurgery you’re having and what part of your body needs treatment.

For example, if you’re having Gamma Knife® treatment for a brain tumor, you’ll lie on a table that’s attached to the Gamma Knife unit with your head facing the unit. The table will slide into the unit, where your treatment will begin. But if you’re having stereotactic body radiation therapy, radiation streams from the arm of a machine.

In general, you can expect your team to:

  • Review what you can expect during treatment.
  • Help you up on the treatment table, the same table used for simulation.
  • Put immobilization devices in place. Again, immobilization helps you to stay very still during treatment, so radiation focuses on the tumor and not on healthy tissue.
  • Demonstrate the intercom system you’ll use if you want to talk to the team once they leave the treatment room.
  • Remind you that you won’t feel anything during treatment, but you may hear machinery moving into place.

How long does it take?

Stereotactic radiosurgery may take one to four hours, depending on the specific treatment you get.


What happens after stereotactic radiosurgery?

You’re able to go home after treatment, but your team may ask you to remain at the treatment facility for 30 minutes to a few hours so they can watch for any side effects.

Radiation side effects are often site-specific, which means you’re most likely to experience side effects in the parts of your body exposed to treatment.

Most often, stereotactic radiation therapy treats issues in your brain, but it may be used for small tumors in certain organs or areas of your body. As a result, you may have different side effects. Fatigue is a common side effect, regardless of the treatment areas. Other common side effects may include:

Risks / Benefits

What are the benefits or advantages of stereotactic radiosurgery?

Benefits and advantages include:

  • It has fewer risks and milder side effects than traditional surgery.
  • It helps providers treat tumors that are very close to major organs or in hard-to-reach places of your body.
  • It can treat very small tumors, abnormalities in your brain and other tumors in your body while minimizing potential damage to healthy tissue.


What are the risks of stereotactic radiosurgery?

Rarely, people who have stereotactic radiosurgery for brain issues may develop late effects, including:

  • Difficulty processing information.
  • Memory loss.
  • Trouble concentrating.

Contact your healthcare provider if you notice symptoms that may be late effects of radiation therapy. They’ll work with you to manage side effects. They may recommend prescribed anti-inflammatory medication and/or speech therapy, occupational therapy or physical therapy.

Recovery and Outlook

How long does it take to recover from stereotactic radiosurgery?

Everyone’s different, but side effects like fatigue, nausea and vomiting typically go away between one or two days to a few weeks.

What’s the success rate for stereotactic radiosurgery?

Success rates vary depending on factors like your overall health and the condition for which you receive treatment. Ask your radiation care provider what you can expect based on your situation.

When To Call the Doctor

When should I see my healthcare provider?

Contact your radiation care provider if you have side effects that are worse than you anticipated.

A note from Cleveland Clinic

Stereotactic radiosurgery focuses tiny, powerful beams of energy on tumors and brain abnormalities. The procedure pinpoints radiation on tumors and brain abnormalities, not on healthy tissue. Depending on your situation, you may only need one treatment session. But stereotactic radiosurgery, like any radiation therapy, can be stressful. You may feel anxious about the process. Your radiation care team understands you may have questions and concerns, so don’t hesitate to ask. Knowing what to expect may help you to feel more at ease.

Medically Reviewed

Last reviewed on 10/09/2023.

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