How Are Brain Tumors Diagnosed
In addition to a complete medical history and physical examination, the brain tumor diagnosis process usually involves several steps which can include a neurological exam, CT Scan, MRI Scan, PET Scan, MRS, a biopsy
or other tests or procedures:
Neurological examination -Your physician tests reflexes, muscle strength, eye and mouth movement, coordination, and alertness.
CT Scan/CAT Scan – (Computed Tomography scan)is 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.
MRI Scan – (Magnetic Resonance Imaging) is 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.
PET Scan – (Positron Emission Tomography) is 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).
MRS – (Magnetic Resonance Spectroscopy) is a procedure that produces images depicting function rather than shape. The equipment requires a special, highly complex facility.
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.
A pathology report contains the analysis of brain tissue taken at the time of a craniotomy or needle biopsy. A pathologist examines the tissue under a microscope. Further tests or analysis may be performed on the tumor tissue. Then the pathologist will write a pathology report, which provides the information needed to make a diagnosis of the tumor type.