What you need to know about a bone scan?
A bone scan (i.e., bone scintigraphy) requires the intravenous injection of a small amount of a radioactive tracer (e.g., technetium-99m [ 99m Tc] methylene diphosphonate [MDP]) that is adsorbed into the hydroxyapatite structure of bone. Areas of increased radiotracer uptake relate to bone that is actively being remodeled such as with infection or tumor. The radiotracer carries a relatively low dose of radioactivity and is extremely unlikely to result in any allergic or adverse reactions. The patient can eat and take medications regularly and is able to continue all daily activities before and after the scan. The scan itself occurs approximately 2 hours after injection of the radiotracer, and the scan time is approximately 30-45 minutes for a whole body scan. Single photon emission computed tomography (SPECT) of specific structures may also be performed to better delineate those structures, especially if the SPECT images are coregistered with computed tomography (CT) images. Three-phase bone scans require initial scanning for approximately 20 minutes at the time of the injection as well as delayed images obtained approximately 2 hours after injection.