Pronunciation: teck-KNEE-shum
Also known as: periodic table element Tc; atomic number 43.
Example: A small amount of technetium is combined with a chemical that preferably attaches itself to cancer cells in a test called immunoscintigraphy. X-rays given off by the technetium are detected with an imaging machine that produces an outline of the tumor. Also, lymph vessels and lymph nodes can be located when a physician injects a technetium solution into an area such as the breast and traces the movement of the compound through the lymph system. This technique is called lymphoscintigraphy.
How it works: Technetium is used in nuclear medicine because it gives off a kind of X-ray that is both easy to detect and comparatively safe for the human body (similar to the X-rays used in mammography, for example). When it is attached to a chemical that accumulates at a site of interest such as a tumor, the radiation it gives off reveals the location of the tumor to instruments outside the body. Technetium diagnoses of cancer and other diseases, not treatment. This is because the type of technetium used (called technetium-99m) loses most of its radioactivity in less than 24 hours and is eliminated from your body after the test. Because it is an artificial element not found in nature except in trace amounts, technetium must be produced within hours of its use.
