Brainstem gliomas Brainstem tumors are more common in childhood than in adults, and the incidence has been estimated to be 9-10 times that of adults. ingraham and Jackson reported 8.8% of 313 and 273 cases of pediatric brain tumors, respectively. There was little gender difference in the tumors, and the high incidence age was 8-9 years, with 67.7% of children aged 6-11 years. Although the tumor sites are divided into midbrain, pontine and medulla, in fact, most of them show infiltrative growth and spread up and down along the nerve fiber bundles, with the pontine extension being the most common. Almost all tumors are gliomas, with astrocytoma and glioblastoma multiforme being the most common, and some of them may be gangliogliomas and ventricular meningiomas. Glioblastoma is the most common type of tumor in the upper brainstem, while glioblastoma is the most common type of tumor in the lower brainstem. Among the 53 cases of brainstem tumors in children, we reported 38 cases (71.7%) of astrocytic grade I-II, 14 cases (26.4%) of glioblastoma multiforme, and 1 case of mixed glioma. 1. Clinical manifestations of brainstem tumors: one or more cranial nerve palsy is often an important feature of brainstem tumors, and 24% of the first symptoms are cranial nerve palsy. The most common cranial nerve damage is adductor nerve, followed by facial nerve and linguopharyngeal and vagus nerves. The symptoms can be inward eye obliquity and diplopia; facial palsy; swallowing and choking; ptosis and loss of pupillary dilated light reflex. When the tumor damages the pyramidal bundle at the same time, crossed palsy (ipsilateral cranial nerve damage combined with contralateral limb hemiparesis) may appear, and the pyramidal bundle signs are often bilateral. Tumor invasion of the cerebellar-dentate nucleus-red nucleus-thalamic tract can lead to cerebellar damage signs (64.6%), which manifest as gait instability, limb ataxia and nystagmus. The incidence of increased cranial pressure was reported to be 15%-23.3% in foreign literature, but 53.1% in our group, which was related to the advanced stage of the disease at the time of diagnosis. A small number of children have mental retardation and mental changes (strong crying or strong laughing, etc.). (1) Lumbar puncture: the amount of cerebrospinal fluid protein was normal or slightly high, and the cell count was normal. (2) Brainstem auditory evoked potential (BAEP): some people reported 6 cases of abnormal auditory potential in 7 cases of childhood brainstem tumors. (3) CT: It shows low or equal density occupancy in the brainstem, or mixed density, and the tumor is more solid and less cystic with heterogeneous enhancement. Due to the influence of posterior cranial fossa artifact, the image of tumor is poor. (4) MRI: astrocytoma is mostly long T1 and long T2 signal, with enlarged brainstem morphology, unclear boundary and heterogeneous enhancement, the degree of which is related to the malignancy of the tumor, and may be accompanied by intra-tumoral hemorrhage and occasional cystic changes. 3. Diagnosis of brainstem tumor: school-age children with inward eye strabismus (diplopia), peripheral facial palsy, slurred speech, swallowing and choking, and unstable walking should think of the possibility of this disease. However, imaging examination cannot fully confirm the diagnosis, because some cases of brainstem demyelination, infection inflammation and vasculitis may be misdiagnosed as brainstem glioma, and unnecessary radiotherapy is taken, which aggravates the clinical symptoms instead. Therefore, stereotactic-guided biopsy of brainstem lesions shows advantages in diagnosis and treatment, which can not only clarify the diagnosis, but also take iodine 125 seed implantation internal radiotherapy at the same time. Therefore, stereotactic-guided brainstem biopsy shows advantages in diagnosis and treatment. The Department of Neurosurgery of the Naval General Hospital has treated more than 90 cases of brainstem lesions with sub-method biopsy diagnosis and achieved relatively satisfactory treatment results, at least the diagnosis is clear. Moreover, the surgical trauma and risk are lower than that of craniotomy. 4.Brain stem tumor treatment: radiation therapy is preferred for substantial tumor with low intracranial pressure and unclear boundary, generally the total amount of radiation should reach 50-55GY, more than this dose will cause radioactive necrosis, the irradiation site is usually localized in the posterior cranial recess tumor bed, some people also think that radiotherapy should include spinal cord. Most patients show improvement of clinical symptoms after radiotherapy, but the remission period usually does not exceed 8 months. In recent years, with the development of radiotherapy technology, the 5-year survival rate of radiotherapy alone has been significantly improved, reaching up to 40%. For those who protrude from the surface of brainstem or have cystic changes, surgery can be considered. The purpose of surgery is to release the compression of brainstem, restore the patency of cerebrospinal fluid circulation and clarify the nature of tumor. As much as possible, the tumor should be removed under microscope without increasing the neurological damage, and postoperative radiation therapy should be used as a supplement. Intraoperative monitoring of brainstem neurological function and resection of tumor with ultrasonic suction (CUSA) and laser (Laser) can reduce postoperative complications and decrease mortality. In our group, there were 47 cases of surgical exploration, 5 cases of biopsy, 35 cases of partial resection, 6 cases of majority resection, and 1 case of subtotal resection, with a mortality rate of 17% at 1 month after surgery. Some people have performed radiotherapy followed by multiple combination chemotherapy for unresectable pediatric brainstem tumors, and the drugs selected include vincristine, carboxin (BCNU), cyclohexylnitrosourea (CCNU), and 5-fluorouracil, but the efficacy is not certain. In addition, stereotactic internal radiotherapy can be considered, and the effect of tumor control is still satisfactory. 5.Prognosis of brainstem tumor: The prognosis of pediatric brainstem glioma is mainly related to the pathological nature, location, size, surgical technique and postoperative adjuvant therapy. 5-year survival rate is generally reported to be 30-40%, 10-year survival rate is 10-20%.