Gamma Knife

Departments of Neurosurgery and Radiation Oncology-Gamma Knife Radiosurgery

The Gamma Knife Center at Roswell Park Cancer Institute is pleased to offer patients the option of minimally invasive Gamma Knife radiosurgery. The Gamma Knife procedure serves as an effective alternative to conventional neurosurgery or traditional radiation therapy in the treatment of certain brain disorders.

Gamma Knife Stereotactic Radiosurgery:

This minimally invasive procedure employs the Leksell Gamma Knife - a revolutionary, state-of-the-art instrument that allows brain tumors (both benign and malignant), arteriovenous malformations (AVMs), and other disorders such as trigeminal neuralgia or tic douloureux to be treated quickly and effectively without opening the skull.

The brain lesion is first visualized using MRI or cerebral angiography. A treatment plan created using a computer workstation operated by a team of neurosurgeons, radiation oncologists and physicists. Then, the Gamma Knife unit is used to deliver 201 intersecting gamma ray beams to the target in the patient's brain with high precision. Because all of the 201 beams are focused on a single point within the tumor, the lesion gets a high dose of radiation that it cannot tolerate; whereas, a thin rim of normal tissue around the lesion gets a much lower dose that it can tolerate.

Indications or Uses

Gamma Knife radiosurgery is most appropriate for those who have benign or malignant brain tumors that are less than about one and one-third inches (3.5 centimeters) in diameter. Tumors and arteriovenous malformations located deep in the brain may be unreachable by conventional surgery. Instead, such lesions may be appropriate targets for treatment with the Gamma Knife. Most of the tumors and conditions that can be treated by Gamma Knife radiosurgery are listed below.

  • Single or multiple metastatic tumors
    a) These are “secondary” brain tumors that have spread from “primary” tumors of the lung, breast, kidney, colon or skin (melanoma) or from other organs
    b) Metastatic tumors are the number one use for the gamma knife
  • Meningioma
  • Acoustic neuroma (vestibular schwannoma)
  • Trigeminal neuralgia (tic douloureux) - one cause of severe facial pain
  • Arteriovenous malformation
  • Glioma (glioblastoma, astrocytoma, oligodendroglioma)
  • Pituitary tumor (adenoma)
  • Craniopharyngioma
  • Hemangioblastoma

Reduced Risks, Rapid Recovery

Since Gamma Knife radiosurgery is performed without incisions or general anesthesia, the usual risks associated with conventional neurosurgery, such as infection and bleeding, are virtually eliminated. Patients are discharged from the Gamma Knife Center on the day of treatment and are usually able to return to their normal activities within 24 hours. While the Gamma Knife stops tumors from growing, it does not always make them shrink or disappear like surgery. For most people, the benefits of treatment are realized over time and results may take from several weeks to several years to develop, depending upon the problem being treated. Following treatment, patients are evaluated serially with MRI scans and neurological assessments at scheduled outpatient visits.

Historical Background

Professor Lars Leksell of the Karolinska Institute in Stockholm, Sweden conceived of and developed the Gamma Knife in the 1950's. After extensive research and evaluation, the first patient was treated in 1968 in Stockholm. To date, over 250,000 patients have been treated worldwide. Gamma Knife technology is approved by the Food and Drug Administration and the results of treatment have been studied in detail and have been published in peer-reviewed medical journals. Gamma Knife radiosurgery is recognized as an effective treatment for brain lesions. Most insurance carriers, including Medicare, cover the procedure.

For More information

If you want to know more about Gamma Knife radiosurgery at Roswell Park Cancer Institute, or would like to refer a patient to the Gamma Knife Center, please send your request for information to or call us at 1-800-ROSWELL.