Differential diagnosis method of glioma

Glioma is the most common type of primary brain tumor. Like other tumors, glioma is formed by the interaction of internal genetic factors and external environmental pathogenic factors. So what are the methods for differential diagnosis of glioma? What results can confirm a glioma?

The differential diagnosis of gliomas requires comprehensive consideration and judgment of the patient's medical history, symptoms, signs, auxiliary examinations, and postoperative pathology. After the patient has clinical symptoms, the most common examinations during the visit include cranial CT and magnetic resonance imaging (MRI). Craniocerebral CT can preliminarily determine whether there is an intracranial mass. Gliomas often appear as intracerebral, low-signal lesions on CT; low-grade gliomas generally have no peritumoral edema, and high-grade gliomas are often accompanied by peritumoral edema.

In addition, CT is better than MRI in detecting whether there is tumor bleeding and calcification. Bleeding in tumor stroke appears as high signal on CT, indicating that the tumor is more malignant. The occurrence of calcification in the tumor indicates that the pathological type of the tumor is likely to be oligodendroblastic. MRI is better than CT examination in showing the location and nature of the tumor. Low-grade gliomas often appear as brain lesions with low T1 signal and high T2 signal on MRI. They are mainly located in the white matter and often have clear boundaries with the surrounding brain tissue on the image. Peritumoral edema is often mild and the lesions are generally not enhanced. High-grade gliomas generally have uneven signals, with low T1 signals and high T2 signals; but if there is bleeding, T1 sometimes also has high signals; tumors often have obvious uneven enhancement; the boundaries between tumors and surrounding brain tissues are unclear; peritumoral edema is more severe. Sometimes, gliomas are not easy to distinguish from other lesions, such as inflammation and ischemia.

Therefore, other tests may be needed, including PET, MRS and other tests, to further understand the sugar metabolism and other molecular metabolism of the lesion, so as to make a differential diagnosis. In addition, sometimes in order to clarify the relationship between the lesion and the function of the surrounding brain tissue, a so-called functional magnetic resonance imaging (fMRI) is also required. Through these tests, we can generally make a preliminary clinical judgment on the location and malignancy of the glioma before surgery. However, the final diagnosis depends on the pathological diagnosis after surgery.