gamma knife

In medicine, the Leksell Gamma Knife is a neurosurgical device used to treat brain tumors with radiation therapy. The device was invented by Lars Leksell, a Swedish neurosurgeon, in 1967 at the Karolinska Institute in Sweden.The Leksell Gamma Knife device contains 201 cobalt-60 sources of approximately 30 curies (1.1 TBq) each, placed in a circular array in a heavily shielded assembly. The device aims gamma radiation through a target point in the patient's brain. The patient wears a specialized helmet that is surgically fixed to their skull so that the brain tumor remains stationary at target point of the gamma rays. A killing dose of radiation is thereby sent through the tumor in one treatment session, while all surrounding brain tissues receive less than a killing dose.
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Gamma Knife A trademark for a radiologic nonsurgical device used in stereotactic radiosurgery. Gamma knife A surgical tool that focuses beams of [more]Gamma Knife - Community and Resources

Radiation therapy in which high-energy rays are aimed at a tumor from many angles in a single treatment session.