>>Bone scintigraphy

Bone scintigraphyBone scintigraphy is commonly used to search for bone metastases of several neoplasms. Since it is highly sensitive, it will frequently be the first sign of a skeleton involvement by the malignant disease. On the other hand, it can be be used to diagnose primary bone tumors. However, these occur mainly in children and young adults. In case of metabolic bone disorders, several typical signs make the bone scintigraphy highly characteristic (image of superscan).

In case of vascular disorders, three phase bone scan including vascular dynamic injection, followed by a blood pool phase and finally static images gives essential information regarding vascular condition of an involved limb, the presence of inflammation and an eventual algodystrophy, which is a frequent complication of several injuries. Moreover, since radiographs do not always clearly demonstrate a site of fracture, an injury due to the practice of sport, or a prosthesis breaking, the high sensitivity of bone scintigraphy can also be helpful in these circumstances.

Finally, tracers, as Gallium, labelled white blood cells and human immunoglobulins are useful to diagnose inflammation, infection and contribute to the differential diagnosis between arthritis and inflammatory bone diseases. Some tracers as Ytrium can also be used for the treatment of inflammatory joint diseases.


Time between tracer injection and bone scintigraphy is +/-3 hours. Bone uptake is maximal after 2 hours. Time between injection and scintigraphy should be at least 2 hours.

Since unbound radiopharmaceutical is excreted by the kidney, to minimize radiation to the bladder, the patient should be encouraged to drink fluids. He should void before initiating the scan, procedure to allow good visualization of the pelvis.

In case of unability to void, views of the pelvis can be non diagnostic and late images (up to 24 hours) can be mandatory.


  • Biphosphonates labelled with 99mTc (99m Technetium) are most widely used : adult dose = 740MBq (20 mCi).
  • Hydroxyethylidene diphosphonate (EHDP).
  • Methylene dihosphonate (MDP).
  • Hydroxymethylene diphosphonate (HMDP).

Alternative agents :

  • 67 Ga (67 Gallium), labelled leucocytes, human immunoglobulins, to look for inflammation or infection, when bone scintigraphy is positive.

Documents in PDF format :

>>Functional imaging atlas in nuclear medicine.