Nuclear Medicine
what is a nuclear medicine exam?
Nuclear medicine imaging uses small amounts of radioactive materials called radiotracers that are typically injected into the bloodstream, inhaled or swallowed. The radiotracer travels through the area being examined and gives off energy in the form of gamma rays which are detected by a special camera and a computer to create images of the inside of your body. Nuclear medicine imaging provides unique information that often cannot be obtained using other imaging procedures and offers the potential to identify disease in its earliest stages.
What are the limitations of General Nuclear Medicine?
Nuclear medicine procedures can be time consuming. It can take several hours to days for the radiotracer to accumulate in the area of interest, and imaging may take up to several hours to perform. In some cases, newer equipment can substantially shorten the procedure time.
The image resolution of nuclear medicine images may not be as high as that of CT or MRI. However, nuclear medicine scans are more sensitive for a variety of indications, and the functional information they yield is often unobtainable by other imaging techniques.
How should I prepare?
You may wear a gown during the exam or be allowed to wear your own clothing.
Women should always tell their doctor and technologist if there is any possibility that they are pregnant or they are breastfeeding. Tell the doctor and the technologist performing your exam about any medications you are taking, including vitamins and herbal supplements. List any allergies, recent illnesses and other medical conditions.
Leave jewelry and other metallic accessories at home or remove them prior to the exam. Such objects may interfere with the procedure.
You will receive specific instructions based on the type of your scan.
In some instances, certain medications or procedures may interfere with the examination ordered
What will I experience during and after the procedure?
Except for intravenous injections, most nuclear medicine procedures are painless. They are rarely associated with significant discomfort or side effects. When the radiotracer is given intravenously, you will feel a slight pin prick when the needle is inserted into your vein for the intravenous line. You may feel a cold sensation moving up your arm when the radiotracer is injected. Generally, there are no other side effects.
When swallowed, the radiotracer has little or no taste. When inhaled, you should feel no differently than when breathing the air around you or holding your breath. With some procedures, a catheter may be placed into your bladder. This may cause temporary discomfort. It is important to remain still during the exam. Nuclear imaging itself causes no pain. However, having to remain still or to stay in one particular position during imaging may cause discomfort.
Unless your doctor tells you otherwise, you may resume your normal activities after your exam. A technologist, nurse or doctor will provide you with any necessary special instructions before you leave. The small amount of radiotracer in your body will lose its radioactivity over time through the natural process of radioactive decay. It may also pass out of your body through your urine or stool during the first few hours or days following the test. Drink plenty of water to help flush the radioactive material out of your body.
What are the benefits vs. risks?
Benefits
Nuclear medicine examinations provide unique information—including details on the function and anatomy of body structures—that is often unattainable using other imaging procedures.
Nuclear medicine scans provide the most useful diagnostic or treatment information for many diseases.
A nuclear medicine scan is less expensive and may yield more precise information than exploratory surgery.
Nuclear medicine offers the potential to identify disease in its earliest stage, often before symptoms occur or abnormalities can be detected with other diagnostic tests.
By detecting whether lesions are likely benign or malignant, PET scans may eliminate the need for surgical biopsy or identify the best biopsy location.
PET scans may provide additional information that is used for radiation therapy planning.
Risks
Because only a small dose of radiotracer is used, nuclear medicine exams have a relatively low radiation exposure. This is acceptable for diagnostic exams. Thus, the radiation risk is very low when compared with the potential benefits.
Nuclear medicine diagnostic procedures have been used for more than five decades, and there are no known long-term adverse effects from such low-dose exposure.
Treatment risks are always weighed against the potential benefits for nuclear medicine therapeutic procedures. Your doctor will inform you of all significant risks prior to the treatment and give you an opportunity to ask questions.
Allergic reactions to radiotracers are extremely rare and usually mild. Always tell the nuclear medicine personnel of any allergies you may have or other problems that may have occurred during a previous nuclear medicine exam.
Injection of the radiotracer may cause slight pain and redness. This should rapidly resolve.
Women should always tell their doctor and radiology technologist if there is any possibility that they are pregnant or they are breastfeeding.