Radiosurgery

Radiosurgery is a form of neurosurgery that uses two or more focused beams of high-energy ionizing radiation to destroy tissue in the brain without a surgical incision and without exposing other tissue to a fatal dose of radiation. It's generally used to treat small areas of the brain where conventional surgery would be dangerous or impractical.
The best known and most used tool is the Gamma Knife, which uses Cobalt-60, a radiation source, in a helmet with channels that can allow the radiation through. It's primarily used on tumors, blood vessel abnormalities, and to treat certain types of behavioral disorders.
Radiosurgery at Wikipedia
Category:Medical procedures