Symptoms of malignant glioma: Clinical manifestations (e.g., headache, vomiting, epilepsy, aphasia, paralysis) are not specific; in other words, it is impossible to determine the benignity or malignancy of a tumor based on the patient’s clinical manifestations. Therefore, the preoperative diagnosis of malignant glioma mainly relies on imaging examinations. Cranial CT (recommended by evidence-based medicine): On CT plain scan, tumor density is heterogeneous, usually hypodense, and high density when combined with hemorrhage or calcification. Peritumor edema and occupying effect are seen, and the lateral ventricle is compressed to become smaller and shifted in the midline. Malignant glioma is commonly associated with hemorrhage, necrosis, and cystic changes. The tumor border is unclear. Enhancement scans show irregular circumferential enhancement. In gliomatosis, there is mostly no enhancement or slight plaque-like enhancement. MRI (highly recommended by evidence-based medicine): MRI scan is usually a mixed signal lesion with iso- or low-signal in T1 phase and inhomogeneous high signal in T2 phase, often with hemorrhage, necrosis or cystic lesions. The peritumor edema and occupational effect are obvious. The tumor often spreads along the white matter fiber bundles. Enhancement shows nodular or irregular ring-like enhancement, while gliomatosis shows no enhancement or slight plaque-like enhancement. Medulloblastoma generally presents as a cerebellar earthworm mass with uniform and marked enhancement, sometimes seen spreading along the cerebrospinal fluid. The magnetic resonance DWI imaging is valuable for differentiating malignant glioma from abscess, DTI can reflect the invasion of nerve conduction bundles by glioma, and BOLD-fMRI can determine the relationship between glioma and functional areas of cerebral cortex. The NAA/Cr, NAA/Cho, and Cho/Cr ratios can identify the degree of benignity and malignancy of glioma, and determine whether there is tumor cell infiltration around malignant glioma. Nuclear medicine imaging (PET-CT): Based on the level of glucose metabolism and amino acid metabolism of the mass, it helps to identify malignant glioma and radiation necrosis. Of course, the most accurate diagnosis is the postoperative pathological diagnosis, therefore, for patients with high suspicion of malignant glioma, families usually take the attitude that they would rather believe it and aggressive surgical treatment.