What are the general methods for diagnosing glioma?

Gliomas originate from glial cells in the brain and are the most common intracranial tumors. Gliomas usually have no typical symptoms in the early stages of the disease, so many patients ignore them and wait until symptoms appear before going for examination, thus missing the best time for treatment. So what are the general diagnostic methods for gliomas?

The diagnosis of glioma is as follows:

1. Nuclear Magnetic Resonance

It is more accurate in diagnosing brain tumors than CT, provides clearer images, and can detect tiny tumors that CT cannot show.

2. Ultrasonic examination

It can help determine the side and observe whether there is hydrocephalus. For infants, B-mode ultrasound scans can be performed through the anterior fontanelle to show tumor images and other pathological changes. So this is a diagnostic method for brain glioma.

3. Radioisotope Scanning (Y-Ray Brain Map)

Tumors that grow quickly 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. More benign gliomas such as astrocytomas have lower concentrations, which are often slightly higher than the surrounding brain tissues, and the images are not clear, and some may be negative findings.

4. Cerebrospinal fluid examination

The pressure of lumbar puncture is usually increased. For some tumors, such as those located on the brain surface or in the ventricles, the amount of cerebrospinal fluid protein may increase, the number of white blood cells may also increase, and some tumor cells may be found. 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 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.

5. Electroencephalogram examination

The EEG changes of gliomas are limited to the changes of brain waves in the tumor site. On the other hand, they are generally widely distributed changes in frequency and amplitude. These are affected by tumor size, infiltration, degree of brain edema, and increased intracranial pressure. Shallow tumors are prone to localized abnormalities, while deep tumors are less likely to have localized changes.