Pet

Positron Emission Tomography otherwise known as PET imaging or PET scan is a diagnostic imaging technique used to generate pictures of the patient’s biological functions, and the metabolic changes of the cells in the body. PET imaging differs from the more traditional diagnostic imaging techniques such as x-ray, MRI and CT scans because it images the body’s basic biochemistry and function rather than imaging the body’s anatomy and structure. This can be useful for detecting biochemical alterations, which in turn can spot disease before changes in anatomy are apparent. It is a valuable tool for those who have different conditions affecting the brain and heart, as well as different types of cancer. It has been in clinical use since the early 1990’s.

The actual procedure involves the use of a small amount of radioactive material, similar to that which is used in other nuclear medicine techniques. This radioactive material is “tagged” or attached to other compounds that are familiar to the body, such as glucose, water, and ammonia. This is then administered to the patient approximately 30-45 minutes before the imaging, usually by intravenous injection. This gives the substance time to travel through the body allowing it to be absorbed by the tissue that is to be examined. The patient is then reclined on a table that slides into the middle of an “open-air” scanner. A collection of radiation detectors in the scanner locate and record the energy that the radioactivity in the body emits and sends the data to a computer, where three- dimensional color-coded images are produced. The average PET scan time is 26-36 minutes, where as the average CT scan is 20-30 minutes.