First, the head gamma knife dose splitting treatment overview: “Gamma knife dose splitting treatment” is a new treatment concept and method, belongs to the gamma knife treatment of a major new progress. “Gamma knife dose-segmentation therapy” not only retains the advantages of gamma knife high-dose focused irradiation, but also absorbs the advantages of repeated irradiation of radiotherapy rays, which can greatly improve the tumor control rate, but also reduce the damage to the normal brain. “Gamma Knife Dose Fractionation Therapy is suitable for all kinds of brain tumors, benign or malignant, especially the larger ones. The common ones are glioma, brain metastases, meningioma, pituitary adenoma, auditory neuroma, etc.; there are also less common intracerebral lymphoma, pineal tumor, chordoma, osteochondroma, nasopharyngeal cancer, maxillary sinus cancer, intraorbital tumor, etc. Gamma knife dose fractionation for brain tumor is the best. “Surgery, radiotherapy and chemotherapy” are the three major weapons for tumor treatment in the trunk. However, the treatment of brain tumor is still mainly based on “surgery + gamma knife”. The main reason is that chemotherapy for brain tumors has very limited efficacy, while radiotherapy for brain tumors has the problem of large side effects. Although head gamma knife also belongs to the category of radiotherapy, it has been transformed into a non-general radiotherapy, a precise radiotherapy guided by stereotactic technology, which belongs to the category of stereotactic radiosurgery and is the “gold standard” of stereotactic radiosurgery, and nowadays head gamma knife has become the main means of brain tumor treatment, and even For a significant number of patients, it has surpassed surgery and become the preferred treatment method. And gamma knife dose fractionation treatment, on the basis of which there has been a new development. The reason why the head gamma knife is superior to other devices including X-knife, radio-wave knife, tommy knife, linear gas pedal, etc. and has become the “gold standard” of stereotactic radiosurgery for brain tumors is that the head gamma knife has three absolute advantages: (1) accurate three-dimensional positioning (2) unparalleled three-dimensional spatial focus of radiation; (3) highly consistent three-dimensional tumor conformation. Head Gamma Knife dose splitting treatment, while having these three advantages, but also the head Gamma Knife a one-time high dose of irradiation, but also changed to repeated medium dose irradiation. This improvement makes head gamma knife treatment not only suitable for smaller tumors, but also for larger tumors will have satisfactory results. The so-called “dose splitting” is to divide the lethal dose of the tumor into several portions and repeatedly irradiate it. It has long been commonly used in conventional radiation therapy, but there is no precedent for “head gamma knife dose fractionation therapy”. The problems and difficulties exist at three levels: (1) the change of treatment concept; (2) the design of specific methods; (3) the summary of practical experience. Dr. Hu Zeyong is the advocate of the concept of “head gamma knife dose splitting treatment”; the inventor and designer of the specific method of “head gamma knife dose splitting treatment”; and the expert of “head gamma knife dose splitting treatment”. “experts, has accumulated a wealth of clinical experience, has been for thousands of patients to solve the disease pain. Dr. Hu Zeyong has been engaged in clinical work in neurosurgery after graduating from graduate school at the end of 1980s, and has been engaged in craniotomy for brain tumor treatment for more than ten years in the early 1990s, participated in the independent research and development and clinical application of the first X-knife in China, and turned to head gamma knife treatment in the mid-1990s, with nearly twenty years of experience in head gamma knife treatment, and has personally provided Tens of thousands of patients to solve the disease pain. Dr. Hu Zeyong, after summing up many years of experience in the application of head gamma knife, the earliest in the head gamma knife scientific community proposed “gamma knife dose splitting treatment”, the relentless pursuit and exploration for the larger volume of brain tumor gamma knife treatment has brought new hope, which has proved to be epoch-making significance. Sixth, the rationale of head gamma knife dose-division therapy head gamma knife through stereotactic spatial focusing method, countless beams of gamma rays converge on the tumor in all directions, a one-time high-dose irradiation, so that tumor degeneration necrosis, shrinkage and disappear. It has the advantages of light trauma, short cycle time and less pain. However, for larger brain tumors, this “one-time high-dose irradiation” can lead to significant side effects, and even intracranial hypertension. The radiobiological theory that “head gamma knife dose fractionation therapy” can reduce these side effects is based on the following: (1) repeated irradiation can re-proliferate the tumor cells remaining from the previous irradiation (reoxygenation of dormant cells) and then kill them; (2) because the tolerance dose of brain tissue to radiation is higher than that of tumor tissue, when the irradiation dose of each time is reduced to between these two, the radiation can be killed. When the irradiation dose is reduced to between these two, the radiation can lethally damage the tumor cells, but only produce sub-lethal damage to normal brain tissue; the former damage is irreversible, while the latter damage can be repaired by itself within the inter-treatment period (more than 6 hours). Seven, the process of head gamma knife dose splitting treatment “Gamma knife dose splitting treatment” the whole course of treatment takes 3-5 days. The basic process is the same as the general gamma knife treatment, including: head frame installation, positioning scanning, treatment planning, treatment implementation. The key technology is the repeated installation of the head frame, the calibration of the head frame position and the distribution of the treatment dose. This requires some proprietary technical guarantees and extensive practical experience. Oral sedative, antiemetic, analgesic and anti-inflammatory medications are routinely administered between treatments to eliminate discomfort. The end of treatment generally does not have too many adverse reactions, you can go straight home to recuperate, and then regularly back to the hospital for review is. Eight, the head gamma knife dose splitting treatment of the ten typical cases (a) low-grade (I-II) glioma: the treatment of glioma, the academic community generally advocate craniotomy, followed by radiotherapy + chemotherapy. The disadvantages are high trauma and severe brain damage. Because most low-grade gliomas are asymptomatic at the early stage of development, by the time they can be detected, the tumors are often huge in size, so the scope of total surgical excision is large and unnecessary brain function damage is common. In fact, low-grade glioma is particularly suitable for head gamma knife dose fractionation treatment, and the treatment effect is surprisingly good, not only can make the tumor disappear, but also without any side damage. The number of patients who have benefited from this treatment is particularly large, but it is not yet widely known. The frontal giant glioma, the tumor completely disappeared 1 year after gamma knife dose fractionation treatment. (B) huge size of brain metastases: brain metastases, refers to tumors of the trunk (such as lung cancer, liver cancer, breast cancer, prostate cancer, etc.) through blood, lymphatic or local invasion, metastases to the brain. Brain metastases should be treated with head gamma knife first, which has been generally recognized by the academic community as a good and fast treatment effect. However, for late detection of brain metastases, the tumor size is already very large, when the tumor diameter >75px, a single gamma knife treatment may have the risk of cerebral edema. In this situation, it is better to choose head gamma knife dose fractionation treatment, which can avoid unnecessary craniotomy. Multiple giant brain metastases in the posterior cranial recess, and the tumor basically disappeared 3 months after gamma knife dose splitting treatment. (3) Brain tumors located in important functional areas: There are more important functional areas in the brain, such as motor-sensory-linguistic area, brainstem and inferior optic thalamus. These parts of the tumor, if you can choose the head gamma knife dose segmentation treatment, not only can achieve better results, but also will greatly reduce unnecessary functional damage. Brainstem cavernous hemangioma, gamma knife dose segmentation treatment after 2 years after the review, the lesion basically disappeared. (iv) Tumor of pineal region The pineal gland is a very small normal structure located in the middle of the brain, whose function is not yet understood, but its surrounding is a high incidence area for tumors, especially in children. Due to the deep location and complex surrounding structures, treatment of pineal region tumors often chooses to do experimental radiotherapy first, and if the effect is good (germ cell tumor), continue radiotherapy with the possibility of cure. If the result is not good, then craniotomy is considered, which is a difficult surgery and difficult to complete, and the long term effect is not satisfactory. In fact, the preferred treatment for tumors in the pineal region is gamma knife dose fractionation, which is also a more sensible choice. After this treatment, there are two outcomes: some tumors disappear completely in a short period of time (1 month) (such as germ cell tumors), and then whole brain and whole spinal cord radiotherapy, combined with chemotherapy, has a higher chance of cure; another part of the tumor, after treatment, does not change much in size, so it can continue to be observed, and some tumors take 2-4 years to become smaller and disappear. As long as the tumor does not increase in size, it is. For tumors in the pineal region, the lesions basically disappeared after 2 months of review after gamma knife dose splitting treatment. (V) Primary lymphoma in the brain In recent years, there is an increasing trend of primary lymphoma in the brain, and inexperienced doctors may treat it as glioma or brain metastasis. Brain lymphoma is characterized by extreme sensitivity to radiotherapy, and radiotherapy plus chemotherapy is the main choice. The direct choice of head gamma knife dose fractionation treatment will achieve very satisfactory results, which can be said to be immediate and the knife to the disease. The greater advantage is: tumor recurrence can be repeated treatment. Tumor residue after craniotomy, Gamma knife dose splitting treatment after 2 months review, the lesion basically disappeared. (VI) Benign tumors with huge volume Benign tumors in the brain commonly include: meningioma, pituitary tumor, auditory neuroma, craniopharyngioma, trigeminal nerve fibroma, cavernous hemangioma and so on. Benign tumors are less likely to recur and can be cured after total excision, so craniotomy is preferred. However, if the surgery is difficult and total excision is difficult; or if the surgery is traumatic and has a high rate of disability and death; or if the patient is not suitable and unwilling to operate, it is best to give priority to head gamma knife treatment. A few special cases, the tumor volume is huge, tumor diameter > 75px, the best choice of head gamma knife dose splitting treatment. (vii) huge volume of skull base malignant tumor The so-called skull base tumor is the tumor occurring under the brain, below; because of the deep location, complex structure and large size of the tumor; therefore, the surgery is difficult, traumatic, high disability rate, high recurrence rate; after surgery often need to be combined with radiotherapy, rarely choose a single head gamma knife treatment. But the emergence of head gamma knife dose-segmentation therapy has changed the situation. The volume of huge skull base malignant tumor, choose head gamma knife dose fractionation treatment, often have satisfactory results, its response is light, less side effects, and the tumor recurrence can be repeated treatment. Thus greatly improving patient satisfaction. These include: skull base chordoma, skull base osteochondroma, skull base metastasis of maxillary sinus cancer, skull base metastasis of nasopharyngeal cancer, etc. (H) Huge cavernous hemangioma of skull base Cavernous hemangioma of skull base often invades the cavernous sinus, develops rapidly and has a wide range of erosion. Surgical resection is very difficult and bleeding. Happy to find in recent years: skull base cavernous hemangioma gamma knife treatment efficacy is very miraculous, so the head gamma knife treatment should be preferred. For huge cavernous hemangioma at the skull base, head gamma knife dose splitting treatment is preferable.