| The first step in diagnosis for how to know if you | | | | as an advantage over CAT scans by institutions that |
| have brain cancer is to evaluate the individual's | | | | use the MRI as the primary method of diagnosis. MRI |
| symptoms. If the symptoms show an indication of brain | | | | is a technique that has been in use since the 1980s. |
| cancer, the tests done to confirm diagnosis include | | | | PET scans are not nearly as commonly used by |
| magnetic resonance imaging (MRI) scan, computed | | | | institutions for determining how to know if you have |
| axial tomography (CAT or CT) scan, and positron | | | | brain cancer. The technique has been in limited use |
| emission tomography (PET) scan. | | | | since the 1950s. It requires the injection of a short-lived |
| CAT scans are specialized x-ray tests combined with | | | | radioactive isotope into the body, which allows for |
| a computer that takes pictures of the inside of the | | | | imaging of the body tissues. It is often combined with |
| brain and brain stem, allowing the doctor to look for | | | | CAT scanning for a broad picture. |
| tumors. The CAT scan differs from standard x-rays in | | | | Skull x-rays were widely used at one time but have |
| that it utilizes a computer to accomplish a | | | | generally been replaced by the above scan |
| cross-sectional view that allows for a much more | | | | procedures. Different institutions will use one or another |
| accurate look at the soft tissues of body parts like | | | | of the scans as the first diagnostic test. |
| that of the brain. A dye is often injected into the body | | | | Any tumor located would be followed by a biopsy of |
| to improve the contrast between abnormal and | | | | the tissue to arrive at an exact diagnosis. A biopsy is a |
| healthy tissue. CAT scanners have been in use since | | | | surgical procedure whereby a small portion of the |
| the mid 1970s. | | | | abnormal tissue is removed and sent to a lab where a |
| MRI scans use magnetic and radio waves to take | | | | doctor can then study is under a microscope. The |
| pictures of the inside of the body. Like the CAT scan, it | | | | type and characteristics of the cells can then be |
| provides images of the soft tissues of the body | | | | determined as to whether it is malignant, degree of |
| allowing the doctor to look for abnormalities. As a tool | | | | invasiveness and growth rate. |
| it will take pictures from any angle which is promoted | | | | |