Intracranial tumors include primary and secondary, the former arising from intracranial structures: skull, meninges, blood vessels, cranial nerves, brain parenchyma, and embryonic remnants. In infants and children, subepidermoid tumors are more common, with higher incidence of astrocytomas, medulloblastomas and ventricular meningiomas. Neuroepithelial tumors used to be called gliomas. They originate from neuroepithelial cells, including astrocytoma, oligodendroglioma, ventricular meningioma, medulloblastoma, etc. They are the most common primary brain tumors, accounting for 40% to 50% of cranial tumors, and are mainly diagnosed by CT and MRI. The more common ones in children include: 1. astrocytoma: astrocytoma is the most common type of neuroepithelial tumor (40%) and accounts for 17% of intracranial tumors. The incidence is slightly higher in males. 75% of adults are located in supratentorial, frontotemporal lobe, and may invade along the corpus callosum to the opposite side. In children, 71% of the tumors are located in the subscripts, and the cerebellar hemispheres account for 80%, followed by the earthworms and brainstem. Pathological classification (according to the degree of differentiation and interstitial degeneration) Grade I tumors with <25% anomalous cells are benign. It includes hairy cell astrocytoma and subventricular giant cell astrocytoma. Grade II low-grade astrocytoma with 25% to 50% intra-tumor anisocytic cells is benign and malignant transitional. It includes pleomorphic yellow astrocytoma. Grade III mesenchymal astrocytoma, with 50% to 75% heteromorphic cells within the tumor, is malignant. Grade IV glioblastoma, with >75% heteromorphic cells within the tumor, is malignant. In children, astrocytomas are mostly found in the cerebellar hemispheres and earthworms. They often compress or obstruct the fourth ventricle causing symptoms such as increased intracranial pressure, gait instability and nystagmus. Brainstem tumors mainly present clinically with dizziness, diplopia and damage to the posterior group of cranial nerves and pyramidal tracts. Cerebellar astrocytomas are located in 80% of the cerebellar hemispheres and 20% in the earthworms. Focal or generalized seizures are the most important clinical manifestations of the disease. Neurological dysfunction and increased intracranial pressure often appear in the later stages of the lesion. 2. Medulloblastoma: It accounts for 4%-8% of intracranial neuroepithelial tumors. It is the most common posterior cranial fossa tumor in children. The typical sites of onset are the cerebellar earth and the top of the four ventricles in children and the cerebellar hemispheres in adults. Medulloblastoma is an extremely malignant tumor. The typical site of origin is the cerebellar earthworm, which tends to protrude into the fourth ventricle and often causes obstructive hydrocephalus. Cerebrospinal fluid dissemination preferably occurs, with extensive implantation in the ventricular system, subarachnoid space, and spinal canal. It shows infiltrative growth with unclear borders, protruding into the ventricle or occasionally with pseudo-envelope and showing clear borders. Tumor cystic changes, calcification and hemorrhage are rare. The tumor cyst, calcification and hemorrhage are rare. There is impaired body balance and poor ataxic movement; signs of cranial hypertension; nerve root irritation causes oblique neck. 3.Ventricular meningioma: It originates from ventricular meningeal cells and mainly occurs in the ventricular system, mostly in the four ventricles, followed by the lateral ventricles, and rarely in the three ventricles. The tumor is swollen and well-defined, with infiltrative growth of interstitial lesions and metastasis by CSF implantation. The four ventricles are more common in children and the lateral ventricles in adults. Supratentorial ventricular meningiomas can occur in the cerebellar hemispheres in both adults and children. 31.3% of supratentorial ventricular meningiomas are located in the brain parenchyma and are the most common supratentorial tumor in pediatric patients. They are most common in the temporo-parieto-occipital junction region. Those in the pediatric brain parenchyma often have large cystic changes and may have calcification. Symptoms depend on the location of the tumor and epilepsy and cranial hypertension are often present. Parenchymal ventricular meningiomas may be associated with mild (grade I) peritumoral edema. In children and adolescents, they are most often located in the temporo-parieto-occipital junction and frontal lobe, and often have large cystic lesions and calcifications, with occasional hemorrhage; in adults, they also occur in the temporo-parieto-occipital junction, but rarely in the frontal lobe, and cystic lesions and calcifications are rare.