Gamma Knife is used to treat brain tumors by administering high-intensity gamma radiation therapy in a manner that concentrates the radiation over a small volume.
A Gamma Knife typically contains 201 cobalt-60 sources of approximately 30 curies each (1.1 TBq), placed in a hemispheric array in a heavily shielded assembly.
Gamma Knife device aims gamma radiation through a target point in the patient’s brain.
The patient wears a specialized helmet that is surgically fixed to the skull, so that the brain tumor remains stationary at the target point of the gamma rays.
Radiation is sent through the tumor in one treatment session, while surrounding brain tissues are relatively spared.
Gamma Knife radiosurgery focuses many beams of gamma radiation on one or more tumors.
Each individual beam is of relatively low intensity, so the radiation has little effect on intervening brain tissue and is concentrated only at the tumor itself.
Gamma Knife radiosurgery lis effective for patients with benign or malignant brain tumors up to 4 cm (1.6 in) in size, vascular malformations such as an arteriovenous malformation, pain from trigeminal neuralgia.
Acute complications following Gamma Knife radiosurgery are rare.