Technetium (99mTc) pentetic acid

Technetium (99mTc) pentetic acid is a radioactive medication used in nuclear medicine for imaging the brain, kidneys, or lungs. It is injected into a vein or inhaled as an aerosol spray. 

Technetium (99mTc) pentetic acid consists of a radioactive isotope of technetium (technetium-99m) bound to a molecule called pentetic acid. Technetium-99m is a man-made radioisotope that gives off gamma rays as it decays. These gamma rays can be detected by a gamma camera to create images of the organs or tissues that take up the medication.

Pentetic acid is a chelating agent that helps the technetium-99m to attach to specific tissues in the body. The way technetium (99mTc) pentetic acid works depends on which organ is being imaged:

• Brain imaging: When injected into a vein, technetium (99mTc) pentetic acid is taken up by the brain tissue. Areas of the brain that are damaged or diseased will take up less of the medication than healthy tissue. This can be seen on a gamma camera scan as dark spots on the image.
• Kidney imaging: When injected into a vein, technetium (99mTc) pentetic acid is filtered out of the blood by the kidneys. The medication is then excreted in the urine. A gamma camera scan can be used to look at the shape and size of the kidneys, as well as how well they are functioning.
• Lung imaging: When inhaled as an aerosol spray, technetium (99mTc) pentetic acid attaches to the surface of the airways in the lungs. A gamma camera scan can be used to look for blockages or other abnormalities in the lungs.