General description

Nuclear medicine imaging uses very small amounts of low energy and short-lived radioactive materials which are introduced into the body. Nuclear medicine examinations use the opposite approach to conventional X-rays.

In X-ray imaging, the radiation exits a machine and passes through the patient's body. In Nuclear Medicine, a radioactive material is introduced into the patient's body and then is detected by special cameras. These materials, called radioactive isotopes, accumulate in one or more organs of interest, depending upon the substance to which they are attached.

The gamma camera then scans the organ or organs of interest, gathering information on the radiation emitted by the isotopes in those structures. Images are then created for evaluation of the organs or organs involved. The areas most commonly scanned in this manner are the lungs, liver, stomach, kidneys, thyroid and bone. Many non-invasive heart studies are performed by using nuclear medicine radioisotopes.

These studies can locate areas of altered function in organs or bones. These scans can show metabolic changes caused by small tumors, fine fractures, or degenerative diseases before they can be detected on an X-ray. There are many nuclear medicine examinations, including:

• Bone imaging
• Brain imaging
• Cardiac imaging
• DEXA scans (bone densitometry)
• Gastrointestinal imaging
• Infection imaging
• Kidney imaging
• Lung imaging
• Lymphoscintigraphy (sentinal node mapping)
• Positron Emission Tomography (PET)
• PET (Positron Emission Tomography)
• Red blood cell volume analysis
• SPECT (Single photon emission computed tomography)
• Thyroid exams (diagnostic and therapeutic)
• Tumor localization and therapy