How is glioma diagnosed

Glioma is a little-known disease. Although most of these tumors are not malignant tumors, they can have a certain impact on human brain nerves. Some glioma patients feel confused after the doctor diagnoses them with glioma. They wonder how they could have such an unheard-of disease. How is it diagnosed? Today we will show you how glioma is diagnosed.

Doctors in regular hospitals usually diagnose gliomas in the following ways:

1. Cerebrospinal fluid examination: The pressure of lumbar puncture is usually increased. For some tumors, such as those located on the surface of the brain or in the ventricles, the amount of cerebrospinal fluid protein may increase, and the number of white blood cells may also increase. Some glioma examinations may show tumor cells. However, for those with significantly increased intracranial pressure, lumbar puncture has the risk of promoting brain herniation. Therefore, it is generally only performed when necessary, such as when it is necessary to distinguish it from inflammation or bleeding. For those with obvious pressure increase, the operation should be cautious and do not release too much cerebrospinal fluid. Mannitol drip is given after surgery and careful observation is required.

2. Ultrasound examination: It can help determine the side and observe whether there is hydrocephalus. For infants, B-type ultrasound scan can be performed through the anterior fontanelle to show tumor images and other pathological changes.

3. EEG examination: On the one hand, the EEG changes of gliomas are limited to the changes in brain waves at the tumor site. On the other hand, there are general and widely distributed changes in frequency and amplitude. These are affected by the size of the tumor, infiltration, degree of brain edema, and increased intracranial pressure. Shallow tumors are prone to localized abnormalities, while deep tumors have fewer localized changes. In more benign astrocytomas, oligodendrogliomas, etc., localized delta waves are mainly manifested, and some epileptic waveforms such as spikes or sharp waves can be seen. Large glioblastoma multiforme can show extensive delta waves, which can sometimes only be determined on one side.

4. Radioisotope scanning: Tumors that grow fast and have abundant blood supply have high blood-brain barrier permeability and high isotope absorption rate. For example, glioblastoma multiforme shows isotope concentration images, and there may be low-density areas in the middle due to necrosis and cysts. It needs to be distinguished from metastatic tumors based on its shape and multiplicity. The concentration of more benign gliomas such as astrocytomas is lower, often slightly higher than the surrounding brain tissue, and the image is not clear, and some may be negative findings.

5. Radiological examination: including skull plain film, ventriculography, computer tomography, etc. Skull plain film can show signs of increased intracranial pressure, tumor calcification and displacement of pineal calcification, etc. Ventriculography can show cerebral vascular displacement and tumor vascular conditions, etc. These abnormal changes are different in different types of tumors in different locations, which can help locate and sometimes even qualitatively identify them. In particular, CT scans have the greatest diagnostic value. The intravenous injection of contrast agent enhanced scanning has a positioning accuracy of almost 100%, and the qualitative diagnosis accuracy can reach more than 90%. It can show the location, range, shape, brain tissue reaction, and ventricle compression displacement of the tumor. However, it still needs to be combined with comprehensive clinical considerations to make a clear diagnosis.

6. Magnetic resonance imaging: It is more accurate than CT in diagnosing brain tumors, and the images are clearer. It can detect tiny tumors that CT cannot show. Positron emission tomography can obtain images similar to CT, and can observe the growth and metabolism of tumors and distinguish benign from malignant tumors.

The above six examinations are the examination items used by doctors to diagnose gliomas. Usually, doctors will choose the necessary examination items based on the patient's condition. Through these examinations, they can accurately determine whether the patient has glioma.