Gamma knife radiosurgery: brain surgery without an incision

Radiosurgery is the precise targeting of ionizing radiation to inactivate or destroy pathologic tissue while sparing adjacent tissue. Like surgery, radiosurgery is done in a single treatment; unlike surgery, radiosurgery does not require an anesthetic or an incision. A specific device for neurosurgery, the gamma knife, uses 201 separate 60Co sources to crossfire gamma rays through a collimator helmet across an intracranial target. This device has been used to treat more than 200 patients at Presbyterian Hospital of Dallas since December 1989. Most patients had either inoperable lesions or residual/recurrent lesions after craniotomy. No patient died and only one developed clinical radionecrosis. Only an overnight hospital stay was required, and patients could resume previous work and activities the day after treatment. Early results parallel reported outcomes in patients treated in Sweden, England, and elsewhere in the United States. In selected patients, the gamma knife is an effective, low-risk, and cost-effective alternative to conventional neurosurgery.