How is a Brain Tumor Diagnosed?

In addition to a complete medical history and physical examination, diagnostic procedures for brain tumors may include the following:

• Neurological examination
  Your physician tests reflexes, muscle strength, eye and mouth movement, coordination, and alertness.
• Computed tomography scan (also called a CT or CAT scan)
  a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general x-rays.
• Magnetic resonance imaging (MRI)
  a diagnostic procedure that uses a combination of large magnets, radio frequencies, and a computer to produce detailed images of organs and structures within the body.
• X-ray
  a diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.
• Bone scan
  pictures or x-rays taken of the bone after a dye has been injected that is absorbed by bone tissue. These are used to detect tumors and bone abnormalities.
• Arteriogram (also called an angiogram)
  an x-ray of the arteries and veins to detect blockage or narrowing of the vessels.
• Myelogram
  a procedure that uses dye injected into the spinal canal to make the structure clearly visible on x-rays.
• Spinal tap (also called a lumbar puncture)
  a special needle is placed into the lower back, into the spinal canal. This is the area around the spinal cord. The pressure in the spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF) can be removed and sent for testing to determine if there is an infection or other problems. CSF is the fluid that bathes the brain and spinal cord.
• Positron emission tomography (PET)
  a type of nuclear medicine procedure. This means that a tiny amount of a radioactive substance, called a radionuclide (radiopharmaceutical or radioactive tracer), is used during the procedure to assist in the examination of the tissue under study. Specifically, PET studies evaluate the metabolism of a particular organ or tissue, so that information about the physiology (functionality) and anatomy (structure) of the organ or tissue is evaluated, as well as its biochemical properties. Thus, PET may detect biochemical changes in an organ or tissue that can identify the onset of a disease process before anatomical changes related to the disease can be seen with other imaging processes such as computed tomography (CT) or magnetic resonance imaging (MRI). UVa has a PET/CT scanner, which combines the advantages of PET and CT scanning to get a more precise look at any potential tumors and their activity.
• Magnetic resonance spectroscopy (MRS)
  a procedure that produces images depicting function rather than shape. The equipment requires a special, highly complex facility.
• Surgical biopsy
  the process of removing at least some of the tumor in order to examine it in a lab. In a craniotomy, the surgeon will also remove as much of the tumor as is safely possible. For tumors in a part of the brain that is difficult to reach, a surgeon may perform a stereotactic biopsy, during which a small sample of the tumor is extracted using a needle.

Diagnosis of a brain tumor depends mostly on the types of cells involved and the tumor location.