Gamma Knife is a type of radiation treatment known as
stereotactic radiosurgery that destroys a brain or pituitary
tumor without opening the skull as in traditional open surgery.
A CT or MRI scan is used to pinpoint the exact location of the
tumor in the brain. High-energy radiation beams are trained on
the tumor from different angles. The radiation destroys the
tumor. Radiosurgery is called "surgery" because it is a one-
session radiation therapy treatment with similar results to an
open surgical procedure. The advantage of knifeless procedures
is that they have fewer complications and the recovery time is
much shorter.