Nuclear Medicine Scans

Nuclear medicine scans are considered safe. Even though they use radioactive materials, the amounts are small. In some cases, your child would be exposed to the same amount of radiation for an x-ray.

The risks of radiation exposure are very low compared to the benefits, such as finding cancer or another disease in its early stages. Nuclear medicine scans have been done for over 50 years, and doctors have not found any long-term bad effects.

Some children are allergic to the tracers used in nuclear medicine scans. This kind of allergy is rare, and the reaction is usually mild, but you should be sure to tell the doctor running the scan if:

• Your child has an allergy to the tracer
• Any other problems have happened during past nuclear medicine scans

Because other ways to take images for your child’s diagnosis may not show the details that these scans do, nuclear medicine scans can be the best way to:

• Detect a disease in its earliest stages
• Confirm a diagnosis
• Check your child’s response to their treatment so far

For some conditions, a nuclear medicine scan can provide the information needed to determine the right treatment for your child.

Your child's doctor will tell you what kind of nuclear medicine scan will be done and what to expect. Some common ways to prepare include:

• Asking questions. If you have questions or concerns about the procedure, be sure to talk to your doctor or healthcare provider.
• Informing your doctor. Before the scans are done, you should verify that the doctor running the scan knows what medicines, vitamins, supplements, or patches your child uses as well as your child’s medical conditions, allergies, and recent illnesses. The doctor can make sure that these things will not interfere with your child’s safety, the test, or its results.
• Following instructions. You may receive instructions about eating and drinking before the scan.  You may also be asked to stop using certain medicines.
• Talking to your child about the scan. If your child is old enough to understand, you can tell them about the test so they know what to expect. An injection of the tracer might hurt like getting a shot. The scanner itself might make them feel closed in and uncomfortable. Most of the time, a parent will be allowed to stay in the room with them during the scan. (Pregnant women cannot stay.) If the scan will take a long time, they will be given breaks.
• Wearing loose, comfortable clothes. Your child might be asked to change into a gown for the test. They should not wear jewelry or metal during the scan.

A nuclear medicine scan uses a special computer and a gamma camera that work together. The gamma camera does not put off any radiation. Instead, it takes pictures of radiation from the tracer and then sends information to the computer. Using the camera’s data, the computer makes detailed images of your child’s body.

Depending on the part of the body being scanned, the gamma camera can make a picture of the structure of an organ, how an organ is working, or the spread of diseased tissue.

For example, a tracer that is mixed with glucose might be used in a PET scanto find the extent of cancer growth. Cancer cells will pick up the glucose faster than regular cells. This test can find cancer in the body because the radioactive material that was absorbed with the sugar will light up.

For the tracer to collect in the body part being studied, you might have to wait a few seconds or even days after the tracer goes into your child’s body. When it is time to start the scan, your child will be placed on an exam table while the gamma camera does its work.

Your child may need to change positions during the study to get a better angle for the camera, but they will need to hold still while the camera is on. Most of the time, the scanning will take less than an hour. Some scans take longer.

Your child will be given breaks or sedated, depending on the length of time needed. They might also be allowed to watch TV or cuddle with a blanket so long as they hold very still.

Before you go, the doctor running the scan will want to check all the pictures. You’ll have to wait for a short time while they make sure that no more pictures are needed.

The tracer will naturally disappear from your child’s body after the scan in a process called radioactive decay. This usually takes less than a day, and your child should drink plenty of water to help flush the tracer out of their body.

Unless the doctor says not to, your child will be able to go back to their usual routine and activities after the scan. If your child was sedated, the doctor will give you specific instructions to follow.

After the nuclear medicine scan is done, the pictures will be studied by a specialist who will write a report. That report and the pictures are then sent to your child’s doctor who will explain them to you.

Your child’s doctor will explain the results of the scan during a follow-up appointment.

MedLine Plus

National Institute of Biomedical Imaging and Bioengineering

A nuclear [NOO-klee-er] medicine scan uses a small amount of radioactive material called a tracer that can be detected by a special camera. This creates a picture of what is going on inside of your child to help diagnose or find the spread of cancers, injuries, and infections. The test is noninvasive and painless, but your child might need an injection to put the tracer into their bloodstream. After the tracer is done collecting in the body part to be scanned, your child will need to hold very still for the gamma camera. When the bone scan, thyroid scan, or other scan is done, a doctor will study the results and share them with your child’s doctor. The tracer will naturally flush out of your child’s body, usually within 24 hours.

Nuclear [NOO-klee-er] medicine scans use small amounts of radioactive material to make pictures of the inside of your child’s body. The radioactive materials, called radiotracers or tracers, are detected and tracked by a special camera and computer, which then make images showing parts of the body and how well they’re working. The scans can help diagnose cancers, injuries, infections, and other problems, especially those that can’t be seen with other imaging studies such as an x-ray, CT scan, or MRI.

Nuclear medicine scans are commonly used to study or diagnose:

• Problems in the kidneys, bladder, and urinary tract
• Heart function and blood flow problems
• Lung and airway function
• Cancers and tumors
• Movement of the digestive system
• Certain infections
• Brain and seizure disorders, such as epilepsy [EH-pih-leh-PSEE]
• How the thyroid gland is working

In children, common nuclear medicine scans include:

• PET scan (positron emission tomography [PAH-zih-TRAWN ee-MIH-shun tuh-MOG-ruh-fee] scan)
• Nuclear bone scan or bone scan
• Gallium [GAL-ee-um] scan
• Thyroid scan

Nuclear medicine scans create images using special equipment that detects radioactivity. A small dose of radioactive material, called a tracer, is given 45 minutes to 1 hour before the procedure. The type of tracer used depends on what area of the body is being tested. There are several ways the tracer can be put into your child’s body:

• Injected (most common).
• Inhaled (breathed in).
• Ingested (eaten with food or drink).
• Put into the bladder through a tube.

The scan doesn’t hurt and usually takes 30 minutes to 1 hour to complete. Your child will need to hold very still while the pictures are taken. Some children need to be sedated with medicine to make them sleepy and help them hold still.