Massachusetts General Hospital Imaging provides nuclear medicine exams on the Mass General main campus and at Mass General West Imaging – Waltham. No matter which facility you come to, our staff places priority on making your journey through the imaging process comfortable, safe, and successful. All images are read by a radiologist with specialty expertise in the area of the body being studied.
Nuclear medicine overview:
- In a nuclear medicine exam, you receive a small amount of radioactive tracer material, known as a radiopharmaceutical, usually as an injection, or sometimes as a gas that you inhale.
- A special camera takes pictures to see how your body absorbs and processes the tracer.
- Nuclear medicine exams are used to detect and monitor many types of cancer; bone and lung scans are two common exams.
- All nuclear medicine scans are read by a radiologist specialty trained in nuclear medicine and dedicated to the specific area of the body being studied.
- We use cutting-edge equipment and technology, including SPECT/CT imaging.
- Radiation exposure from tracers is minimal, and we carefully tailor the dose to each patient, using as little radiation as possible without losing image quality.
- A nuclear medicine scan can take as little as two hours, but some scans require that you leave and come back later that day, or even on consecutive days. Some exams require you to fast ahead of time, while others do not. You will receive specific instructions at the time your exam is scheduled.
- The camera may rotate around you, or you may be asked to shift position.
- The tracer will lose its radioactivity, usually over the first 24 hours following the test, and pass out of your body naturally.
Nuclear medicine in depth
What is a nuclear medicine scan?
Nuclear medicine is a subspecialty within the field of radiology that uses very small amounts of radioactive material called a radiopharmaceutical or radiotracer to diagnose disease and other abnormalities within the body.
Depending on the type of nuclear medicine scan you are undergoing, the radiotracer is injected into a vein, swallowed by mouth, or inhaled as a gas and eventually collects in the area of your body being scanned, where it gives off energy in the form of gamma rays. This energy is detected by a device called a gamma camera and/or probe. These devices work together with a computer to measure the amount of radiotracer absorbed by your body and to produce special pictures offering details on both the structure and function of organs and other internal body parts.
Physicians use nuclear imaging to visualize the structure and function of an organ, tissue, bone or system of the body. Nuclear medicine scans are performed to:
- Analyze kidney function
- Scan lungs for respiratory and blood flow problems
- Identify blockage in the gallbladder
- Evaluate bones for fracture, infection, arthritis and tumors
- Determine the presence or spread of cancer
- Identify bleeding into the bowel
- Locate the presence of infection
- Measure thyroid function to detect an overactive or under-active thyroid
- Investigate abnormalities in the brain
Because the doses of radiotracer administered are small, diagnostic nuclear medicine procedures result in minimal radiation exposure. Thus, the radiation risk is very low compared with the potential benefits. Nuclear medicine has been used for more than five decades, and there are no known long-term adverse effects from such low-dose exposure. Allergic reactions to radiopharmaceuticals may occur but are extremely rare.
Women should always inform their physician or radiology technologist if there is any possibility that they are pregnant or if they are breastfeeding their baby.
What should I expect BEFORE my nuclear medicine scan?
You will receive specific instructions based on the type of scan you are undergoing. In general, the following guidelines apply to all scans.
- Medications: You should inform your physician of any medications you are taking as well as vitamins and herbal supplements and if you have any allergies. Also inform your doctor about recent illnesses or other medical conditions. Upon checking in, you will be asked to provide a list of medications you are currently taking and also a list of known allergies.
- Food and drink: Most nuclear medicine procedures do not require patients to fast, however there are some that do. Specific instructions will be provided upon scheduling of these procedures.
- When to arrive: Please arrive 30 minutes prior to your appointment time.
- What to wear: You will wear your own clothing during the scan, therefore please wear something without metal clasps or zippers, as they will interfere with the study. Jewelry and other accessories should be left at home if possible, or removed prior to the scan as well.
What will I experience DURING my Nuclear Medicine scan?
- Scanning: You will be positioned on an examination table. If necessary, a technologist will insert an intravenous (IV) line into a vein in your hand or arm.
Depending on the type of nuclear medicine scan you are undergoing, the dose of radiotracer is then injected intravenously, swallowed by mouth or inhaled as a gas.
It can take several seconds to several days for the radiotracer to travel through your body and accumulate in the organ or area being studied. As a result, imaging may be done immediately, a few hours later, or even several days after you have received the radioactive material.
When it is time for the imaging to begin, the gamma camera will take a series of images. The camera may rotate around you or it may stay in one position and you will be asked to change positions in between images. While the camera is taking pictures, you will need to remain still for brief periods of time. It is important that you remain still while the images are being recorded. Though nuclear imaging itself causes no pain, there may be some discomfort from having to remain still or to stay in one particular position during imaging.
If a probe is used, this small hand-held device will be passed over the area of the body being studied to measure levels of radioactivity. Other nuclear medicine tests measure radioactivity levels in blood, urine or breath.
- Length of scan: The length of time for nuclear medicine procedures varies greatly, depending on the type of scan. Actual scanning time for nuclear imaging scans can take from 20 minutes to several hours and may be conducted over several days. You will be given specific information depending on the type of study you are having.
What should I expect AFTER my Nuclear Medicine scan?
- Instructions: When the scan is completed, you may be asked to wait until the technologist checks the images in case additional images are needed. If you had an IV line inserted for the procedure, it will be removed. Through the natural process of radioactive decay, the small amount of radiotracer in your body will lose its radioactivity over time. In many cases, the radioactivity will dissipate over the first 24 hours following the test and pass out of your body through your urine or stool. You may be instructed to take special precautions after urinating, to flush the toilet twice and to wash your hands thoroughly. You should also drink plenty of water to help flush the radioactive material out of your body.
Unless your physician tells you otherwise, you may resume your normal activities after your nuclear medicine scan.
- Exam results: All Nuclear Medicine scans are read by a Mass General radiologist specialty trained in nuclear medicine imaging and dedicated to the specific area of interest for your study.
Rapid results are essential not only for your peace-of-mind, but also for your physician to begin planning your treatment immediately, if necessary. After the scan has been read the results are sent to your physician, who will discuss them with you.
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