Whole-Body Bone Scan (Nuclear Medicine)

What it is

An x-ray shows the shape of bone. A bone scan shows its activity. A small amount of a radioactive tracer is injected into a vein, circulates, and binds to bone in proportion to how much repair and turnover is happening there. A gamma camera then detects the emissions and builds an image of the whole skeleton in one pass, front and back. Areas of unusually high uptake — "hot spots" — mark where something is going on; areas of low uptake can matter too. The strength of the study is coverage: it surveys every bone at once rather than one region, which is exactly why it is used when the location of a problem is not known.

Why it is done

• To search the whole skeleton for spread of cancer from elsewhere in the body, or for cancer arising in bone
• To investigate unexplained bone pain when x-rays look normal
• To find stress fractures and other subtle fractures, which can be invisible on plain films early on
• To look for bone infection, or for changes around an existing joint replacement

What to expect

This is a two-part appointment with a long gap in the middle. The tracer is injected first, and then it takes a few hours — RadiologyInfo gives roughly two to four — for it to circulate and bind to bone. Many departments let patients leave and come back. You will usually be asked to drink fluids and empty your bladder before imaging, since tracer clears through the kidneys and a full bladder obscures the pelvis. Imaging itself means lying still on a table while the camera passes slowly over you; it is painless but takes time, and stillness is required. Some studies add extra image sets taken right at the time of injection, or add a rotating three-dimensional set over one region. The tracer decays and clears on its own over the following day or so.

Questions worth asking

• Is the radiopharmaceutical billed separately from the imaging, and what is that line?
• If additional images or a three-dimensional set over one area are added, do those generate their own charges?
• The appointment spans several hours — am I being billed for one visit or two?
• Is the nuclear medicine physician's interpretation a separate professional fee from the facility's technical charge?