Stereotactic radiosurgery - CyberKnifeStereotactic radiotherapy; SRT; Stereotactic body radiotherapy; SBRT; Fractionated stereotactic radiotherapy; SRS
Stereotactic radiosurgery (SRS)is a form of radiation therapy that focuses high-powerenergy on a small area of the body. Despite its name, radiosurgery is a treatment, not a surgical procedure. Incisions (cuts) are not made on your body.
More than one system is used to perform radiosurgery. This article is about radiosurgery using CyberKnife.
During treatment you lie on a table,whichslides into a machine that delivers radiation.
- A robotic arm controlled by a computer moves around you. It focuses radiation exactly on the area being treated.
- You are not put to sleep. The treatment does not cause pain.
The nurses and doctorscan see you on cameras. They can hear you and talk with you on microphones.
Each treatment takes about 30 minutes to2 hours. Some patients receive more than one treatment session, but usually no more than five sessions.
Why the Procedure Is Performed
SRStargets and treats an abnormal area without damaging nearby healthy tissue. SRS is more likely to be recommended for patients who are at high risk of surgery. These patients include the elderly or those who are very ill.
CyberKnifeis often used to slow the growth of small, deep brain tumors that are hard to remove during surgery that involves incisions.
Tumors of the brain and nervous system that can be treated using CyberKnife include:
- Cancer that has spread (metastisized)to the brain from another part of the body
- A slow-growing tumor of the nerve that connects the ear to the brain (acoustic neuroma)
- Pituitary tumors
- Spinal cord tumors
Other cancers that can be treated include:
- A type of skin cancer (melanoma) that involves the eye
Other medical problems treated with CyberKnife are:
- Blood vessel problems such as arteriovenous malformations
- Parkinson disease
- Severe tremors (shaking)
- Some types of epilepsy
- Trigeminal neuralgia (severe nerve pain of the face)
SRSmay damage tissue around the area being treated. As compared to other types of radiation therapy, CyberKnife treatment is much less likely to damage nearby healthy tissue.
Brain swelling may occur in people who receive treatment to the brain. Swellingusually goesaway without treatment. But some people may need medicines to control this swelling. In rare cases, surgery with incisions (open surgery) is needed to treat the brain swelling caused by the radiation.
Before the Procedure
The day before your procedure:
- Do not use any hair creams or hair spray if CyberKnife surgery involves your brain.
- Do not eat or drink anything after midnight unless told otherwise by your doctor.
The day of your procedure:
- Wear comfortable clothing.
- Bring your regular prescription medicines with you to the hospital.
- Do not wear jewelry, makeup, nail polish, or a wig or hairpiece.
- You will be asked to remove contact lenses, eyeglasses, and dentures.
- You will change into a hospital gown.
- An intravenous (lV) line will be placed into your arm to deliver contrast material, medicines, and fluids.
After the Procedure
Often, youcan go home about1 hour after the treatment. Arrange ahead of timefor someone to drive you home. You can go back toyour regular activities the next day if there are no complications such as swelling. If you have complications, you may need to stay in the hospital overnight for monitoring.
The effects ofCyberKnife treatmentmay take weeks or months to be seen. Prognosis depends on the condition being treated. Your health care provider will likely monitor your progress using imaging tests such as MRI and CT scans.
Chang EF, Quigg M, Oh MC, et al. Epilepsy Radiosurgery Study Group. Predictors of efficacy after stereotactic radiosurgery for medial temporal lobe epilepsy. Neurology. 2010;74:165-172.
Ewend MG, Morris DE, Carey LA, et al. Guidelines for the initial management of metastatic brain tumors: role of surgery, radiosurgery, and radiation therapy. J Natl Compr Canc Netw. 2008;6:505-513.
Suh JH. Stereotactic radiosurgery for the management of brain metastases. N Engl J Med. 2010;362:1119-1127.
Welling DB, Packer MD. Stereotactic radiation treatment of benign tumors of the cranial basae. In: Flint PW, Haughey BH, Lund VJ, et al., eds. Cummings Otolaryngology: Head & Neck Surgery. 5th ed. Philadelphia, PA: Elsevier Mosby; 2010:chap 179.
Review Date: 3/8/2013
Reviewed By: Luc Jasmin, MD, PhD, Department of Neurosurgery, Cedars Sinai Medical Center, Los Angeles and Department of Anatomy, University of California, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.