Although the gamma knife is called “knife”, but not a real scalpel. To be precise, the scientific name of gamma knife is gamma stereotactic radiation therapy system, which belongs to the category of precision radiotherapy. It uses the ionizing radiation effect of gamma rays to kill tumor cells for the purpose of treating tumors. It is called a knife because the effect of its treatment of tumors is similar to that of a scalpel, which can completely eliminate the local tumor. In the cross and rotation gamma knife accurately kill tumors Gamma knife has incomparable advantages compared with traditional radiotherapy. Traditional radiotherapy is like ordinary light, the irradiation range is wide, and both normal and tumor tissues are irradiated during treatment. If the tumor location is deeper, the radiation has been attenuated to a negligible degree after reaching the tumor location, so naturally it cannot play a therapeutic effect, and the normal tissues will be damaged instead. For this problem, medical experts have done a lot of research and finally came up with a method to cross the radiation to a point through different directions, which is the location of the tumor. For example, if a tumor is located in the head, a dose is shined in through the forehead, and the dose unit is 2 Gorey (radiation dose unit). If the radiation therapy is carried out by crossing the two channels above the forehead and ear, the radiation dose to the tumor at the crossover point is doubled, while the normal tissue is not affected, and the tumor is illuminated with more doses by choosing several more channels. In addition to the crossover function, the second advantage of the gamma knife is rotation. When the gamma knife rotates, the focus is always on the tumor, while the normal tissue is only momentarily irradiated, and the damage is much less. Gamma knife head and body tumors can be done Head treatment is broader, for example, benign tumors, including meningioma, pituitary tumors, auditory neuroma, etc.; malignant tumors are mainly gliomas, brain metastases, etc.; part of the vascular malformation, as well as trigeminal neuralgia and some epileptic patients can also be treated. The treatment range of the body is broader, more used is lung cancer; followed by the digestive system, such as common liver cancer; urological system tumors are also Gamma Knife is better at treating, such as kidney tumors, adrenal tumors; retroperitoneal, mediastinal parts of the lymph node metastasis cancer, bone metastasis cancer of the spine can also be treated by Gamma Knife.