How gamma knife surgery treats brain tumors

By Jason Howland

It's a form of brain surgery without any incisions. Patients with brain tumors, both benign and malignant, often are candidates for a noninvasive procedure called gamma knife stereotactic radiosurgery. It pinpoints high doses of radiation at the tumor with little impact to surrounding healthy tissue.

Watch this "Mayo Clinic Minute" video to hear Bruce Pollock, M.D., a Mayo Clinic neurologic surgeon, explains the procedure:

It's called gamma knife surgery, but there's no cutting involved.

"Gamma knife radiosurgery is the precise delivery of radiation to some imaging-defined target so we're able to treat benign or malignant tumors within the brain," says Dr. Pollock.

It's been used at Mayo Clinic for 30 years as an alternative to open brain surgery.

"We're performing an outpatient-based procedure that doesn't require an incision and has no risks of infections," says Dr. Pollock.

The patient's head is held still during the procedure with a headframe, which also serves as a map for the radiation. Using 3D imaging — typically an MRI — as a guide, the gamma knife is targeted directly at the tumor.

"The mechanical accuracy of the device is measured as a fraction of a millimeter," says Dr. Pollock.

And with no hospital stay and minimal side effects, it's a procedure that is efficient and can be lifesaving.

"For malignant tumors, the success rate per tumor typically is on the order of 90% or more. For benign tumors that are well-selected, the success rate really ranges up to about 95% to 97%," says Dr. Pollock.

Learn more

Learn more about brain tumors and gamma knife stereotactic radiosurgery, and find a brain tumor clinical trial at Mayo Clinic.

A version of this article was originally published on the Mayo Clinic News Network.