Nuclear medicine looks at how organs and cells function within your body. Most other diagnostic imaging tests, such as an MRI or X-ray, reveal the anatomy, nuclear medicine shows both anatomy and function. It uses the radiopharmaceutical to target a specific area of the body and asks it to ‘show us’ where the area of concern is. Even if there is a very small change that would be difficult to see on other imaging types, Nuclear Medicine will identify the area and give information about what is happening on a cellular level. This is also why Nuclear Medicine is sometimes also called molecular imaging. Newer technologies such as SPECT/CT and PET/CT create three-dimensional (3D) images that the care team can use. 

Nuclear Medicine uses small amounts of radioactive materials, or radiopharmaceuticals, to create images based on how your body is working. An MRT will introduce them into your body by injection, swallowing or inhalation. The radiopharmaceuticals travel through the body and accumulate in the area of interest. Different types of radiopharmaceuticals will accumulate in different areas. The appropriate one is chosen based on what your physician wants to see. After the injection and the correct amount of time has passed, the MRT will use a specialized camera (gamma camera or PET scanner) to detect the radiation coming from your body.  The gamma camera software then transforms the radiation measurements into images, which are sent to a computer for the radiologists and other care providers in your care team to look at.    

When you come to the nuclear medicine department, your MRT will assess the order from your doctor and may ask you some clarifying questions before they begin the test. The MRT will introduce the radiopharmaceutical into your body, most commonly by an intravenous (IV) injection. Radiopharmaceuticals typically do not have any side effects. However, if you do feel anything at all during or after an injection, you should tell your MRT so that they can assess you. Sometimes there is a waiting period between this injection and when they take the images. This all depends on the test that is ordered. When it is time, the MRT will position you on the table to take the images. Sometimes you may have to hold your breath for a few seconds, depending on the image being taken. Nuclear Medicine tests tend to take longer than normal x-rays, and it is important to stay still during these images. Your MRT will work with you to make sure you are as comfortable as possible to get the best images. Once the images are complete, your MRT will give you any aftercare instructions that may be necessary because of the radiopharmaceutical given to you. 

The short answer is yes. Different radiopharmaceuticals stay in the body for different time periods. Some may be in your body for a few hours while some may last a couple of days. The radiopharmaceutical leaves your body through the same routes all other waste does. There will be no visible changes to your body, and you can go about life as normal. If you plan on traveling or crossing any borders in the weeks after your test, please notify the MRT. They will advise you on any necessary considerations. Some radiation detection machines at these travel sites are very sensitive. The MRT will give you a letter or card indicating you have had a nuclear medicine test done.