Bone Scan Periprocedural Care

Updated: Mar 31, 2020
  • Author: Thomas F Heston, MD, FAAFP, FASNC, FACNM; Chief Editor: Mahan Mathur, MD  more...
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Periprocedural Care


Gamma cameras and PET scanners are the 2 basic types of cameras used to image the radioactive decay from the radiotracers utilized in bone scintigraphy.

Gamma cameras contain a sodium iodide crystal that is approximately 1-cm thick and 25-40 cm in diameter or a rectangular shape of 40-50 cm2. [12] A collimator helps ensure that the gamma rays hit the crystal close to a perpendicular 90° angle. The crystal scintillates when hit by gamma rays from the Tc-99m. These scintillations are then detected by photomultiplier tubes, which convert the scintillations to digital data. Gamma cameras used in bone scanning may be configured as a single head (one large crystal), dual headed (2 large crystals), or triple headed (3 large crystals). Newer gamma cameras being developed incorporate cadmium-zinc-telluride solid-state detectors, which may decrease imaging time and radiotracer dose.

PET scanners operate in a similar fashion to gamma cameras; however, they typically contain several small crystals that form a ring around the patient, which can increase resolution while decreasing imaging time. Several different salt crystals can be used. Although sodium iodide can be used, PET scanners more commonly contain bismuth germanate or lutetium oxyorthosilicate. Most PET scanners today are hybrid PET combined with CT scanners, a PET/CT camera.


Patient Preparation

Prior to undergoing any medical procedure, patients should be fully informed as to the reason for the procedure, the alternatives, the benefits, and risks. The reason, alternatives, and benefits of a bone scan are patient-specific and dependent upon the clinical situation. There are no laboratory tests required prior to a bone scan. A woman who is unsure if she is pregnant may need to undergo a urine pregnancy test bwfore the procedure.

After the decision is made to proceed with a bone scan, the patient needs to be told how to prepare for the scan and what to expect on the day of the study. There is no specific preparation necessary for a radionuclide bone scan when using the tracers that map calcium metabolism, Tc-99m MDP or F-18 NaF. Patients should continue taking their medications normally and eating normally. It is helpful to stay well hydrated, since these radiotracers are eliminated from the body in the urine.

Caution is urged in women who are or may be pregnant, as there is a theoretical risk from radiation to the fetus. Although adverse effects have not been proven, it is extremely rare for a pregnant woman to undergo a bone scan.

Occasionally, women who are breastfeeding need to undergo a bone scan. Because a small amount of the radiotracer used in the study may end up in the breast milk, it is common for the woman to stop breastfeeding for about a day after the scan. The recommendations vary according to the specific radiotracer used; however, in most cases, breastfeeding is interrupted for only 24 hours or less. During this time, the mother dumps her breast milk, gives her baby the stored up milk, and resumes normal breastfeeding the next day.

After a bone scan, a small amount of the radiotracer remains in the patient and emits radiation. The amount is very small, and patients are safe to go about their routine activities after the procedure. However, it is important to keep in mind that patients may set off sensitive radiation detectors at border crossings for several days after the procedure. Getting a note from the clinic performing the procedure that includes the study performed and the radiotracer utilized can help prevent any false alarms by security personnel. Also, it is recommended to avoid close contact with a child for 1 hour after a bone scan with Tc-99m MDP; there is no restriction for patients undergoing a bone scan with F-18 NaF.