Bone scan (skeletal scintigraphy) utilizes nuclear medical technologies
A bone scan is an important spinal diagnostic test that can detect areas of increased activity in bone, such as from a spinal fracture, infection, or tumor. A bone scan is also called skeletal scintigraphy. Bone scans can detect changes in your bones before any structural changes can be seen. For example, this test can detect an infection in the bone weeks before it could be seen on a conventional x-ray.
A bone scan is usually performed in a hospital or a large radiology clinic where nuclear medical procedures are performed.
About Bone Scans
The test uses a small amount of a radioactive tracing material called a radiotracer or nuclide that is injected intravenously a few hours before the scan is performed. During this wait, the radiotracer collects in your bones where they will emit small amounts of radioactive energy. More of the tracer is taken up in areas of your bones that are inflamed or damaged. During the actual test, a gamma ray scanner sweeps over your body and detects this energy from the areas where the radiotracer collected. This information is sent to a computer, which produces an image.
A bone scan produces a picture of your bones that can reveal 'hot' and 'cold' spots. Hot spots appear darker on the image and are areas where a lot of the radiotracer has been taken up. Cold spots appear light and are where the bone absorbed less of the tracing element.
The amount of radiotracer used is very small; it amounts to less radioactivity than that of an x-ray. The radiotracer breaks down quickly and is eliminated from your body in one to two days.
What to Tell Your Physician
It is important that the physician who orders the bone scan knows ahead of time if you have any of conditions listed below. Depending on your personal medical history, your physician may need to provide you with special pre-test instructions and/or relay particular information to the radiologist.
- Allergy to contrast media, or other allergies (eg, latex)
- Difficulty urinating
- Unable to lie on your back or lie still
*If you are breastfeeding, you should use formula to feed your baby for a few days after the test.
How Should I Prepare for a Bone Scan?
- You do not need to fast before the scan.
- Do not use any medications that contain bismuth for several days before the scan is done. This includes Pepto-Bismol and similar products.
- Do not have a bone scan within a few days of having an x-ray that involves using a barium contrast material. Both bismuth and barium can throw off the results of the bone scan.
- Before the imaging, you will be asked to remove all metal objects such as jewelry, dentures, and hairpins.
- You will be given a gown to wear.
- The scan will last about an hour.
- You can drive yourself to your appointment and back home again.
How is a Bone Scan Performed?
The radiotracer is injected through an intravenous line that is inserted into your arm or hand. It takes a few hours for the tracer to circulate and collect in your bones. During this time you may be able to go have lunch or run an errand. You will be asked to drink plenty of water during this time. Before the scan is performed, you will be asked to empty your bladder.
- For some bone scans, images are taken while the racer is being injected, immediately afterward, and again 3 to 5 hours later. This is called a three-phase bone scan.
The machine is shaped like a box with a tunnel through it. You lie on a table that passes through the tunnel while the scan is being done. You may need to be repositioned for some parts of the scan so that your bones can be scanned from another angle. While the images are being taken, you will be asked to hold very still.
After a Bone Scan
- After the scan, you are asked to wait while the technician checks the scans to see if additional images are needed.
- For 24- to 48-hours after the bone scan, you will be very slightly radioactive. However, you are in no danger nor is anyone around you. The radioactivity will pass out of your body in a day or two.
- The bone scan images are evaluated by a radiologist who specializes in nuclear medicine. He or she will send a report to your physician or spine surgeon who ordered the test.
Radiological Society of North America, Inc. (RSNA). Skeletal Scintigraphy (Bone Scan). June 3, 2014. http://www.radiologyinfo.org/en/info.cfm?pg=bone-scan. Accessed February 12, 2015.