Why it's done

Gamma Knife radiosurgery is often a safer alternative to standard brain surgery (neurosurgery), which requires incisions in the skull, membranes surrounding the brain and brain tissue. This type of radiation treatment is usually performed when:

  • A tumor or other abnormality in the brain is too hard to reach with standard neurosurgery
  • A person isn't healthy enough to undergo standard surgery
  • A person prefers a less invasive treatment

In some cases, Gamma knife radiosurgery may have a lower risk of side effects compared with other types of radiation therapy.

Gamma Knife radiosurgery is most commonly used to treat the following conditions:

  • Brain tumor. Radiosurgery is useful in the management of small noncancerous (benign) and cancerous (malignant) brain tumors.

    Radiosurgery damages the genetic material (DNA) in the tumor's cells. The cells lose their ability to reproduce and may die, and the tumor may gradually shrink.

  • Arteriovenous malformation (AVM). AVMs are abnormal tangles of arteries and veins in your brain. In an AVM, blood flows from your arteries to veins, bypassing smaller blood vessels (capillaries). AVMs may disrupt the normal flow of blood and lead to bleeding.

    Radiosurgery destroys the AVM and causes the blood vessels to close off over time.

  • Trigeminal neuralgia. Trigeminal neuralgia is a disorder of one or both of the trigeminal nerves, which relay sensory information between your brain and areas of your forehead, cheek and lower jaw. This nerve disorder causes disabling facial pain that feels like an electric shock.

    After treatment, many people will experience pain relief within a few days to a few months.

  • Acoustic neuroma. An acoustic neuroma (vestibular schwannoma) is a noncancerous (benign) tumor that develops along the nerve of balance and hearing leading from your inner ear to your brain.

    When the tumor puts pressure on the nerve, a person can experience hearing loss, dizziness, loss of balance and ringing in the ear (tinnitus). As the tumor grows, it can also put pressure on the nerves affecting sensations and muscle movement in the face.

    Radiosurgery may stop the growth of an acoustic neuroma.

  • Pituitary tumors. Tumors of the bean-sized gland at the base of the brain (pituitary gland) can cause a variety of problems. The pituitary gland controls hormones in your body that control various functions, such as your stress response, metabolism and sexual function.

    Radiosurgery can be used to shrink the tumor and lessen the disruption of pituitary hormone regulation.

Sept. 14, 2016
References
  1. Stereotactic radiosurgery overview. International RadioSurgery Association. http://www.irsa.org/radiosurgery.html. Accessed May 26, 2016.
  2. Gamma Knife surgery. International RadioSurgery Association. http://www.irsa.org/gamma_knife.html. Accessed May 26, 2016.
  3. Stereotactic radiosurgery. American Association of Neurological Surgeons. http://www.aans.org/Patient%20Information/Conditions%20and%20Treatments/Stereotactic%20Radiosurgery.aspx. Accessed May 26, 2016.
  4. Chen CC, et al. Stereotactic cranial radiosurgery. http://www.uptodate.com/home. Accessed May 26, 2016.
  5. Stereotactic radiosurgery (SRS) and stereotactic body radiotherapy (SBRT). Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?PG=stereotactic. Accessed May 26, 2016.
  6. Arteriovenous malformations and other vascular malformations of the central nervous system fact sheet. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/avms/detail_avms.htm. Accessed May 26, 2016.
  7. NINDS trigeminal neuralgia information page. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/trigeminal_neuralgia/trigeminal_neuralgia.htm. Accessed May 26, 2016.
  8. Vestibular schwannoma (acoustic neuroma) and neurofibromatosis. National Institute on Deafness and Other Communication Disorders. http://www.nidcd.nih.gov/health/hearing/pages/acoustic_neuroma.aspx. Accessed May 26, 2016.
  9. Gamma Knife. Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?pg=gamma_knife. Accessed May 26, 2016.
  10. NINDS pituitary tumors information page. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/pituitary_tumors/pituitary_tumors.htm. Accessed May 26, 2016.
  11. Ballonoff A. Acute complications of cranial irradiation. http://www.uptodate.com/home. Accessed May 26, 2016.
  12. A typical treatment day. International RadioSurgery Association. http://www.irsa.org/treatment.html. Accessed May 26, 2016.
  13. Neurological diagnostic tests and procedures. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/misc/diagnostic_tests.htm. Accessed May 26, 2016.
  14. Link MJ (expert opinion). Mayo Clinic, Rochester, Minn. June 27, 2016.