A bone scan is an imaging test that shows areas of increased or decreased bone turnover (metabolism).
Scintigraphy - bone
A bone scan involves injecting a radioactive material (radiotracer) into a vein. The substance travels through the bloodstream to the bones and organs. As it wears away, it gives off radiation. This radiation is detected by a camera that slowly scans your body. The camera takes pictures of how much radiotracer collects in the bones.
If a bone scan is done to see if you have a bone infection, images may be taken shortly after the radioactive material is injected and again 3 to 4 hours later, when it has collected in the bones. This is called a 3-phase bone scan.
To evaluate metastatic bone disease, images are taken only after the 3 to 4 hour delay.
The scanning part of the test will last about 1 hour. The scanner's camera may move above and around you. You may need to change positions.
You will probably be asked to drink extra water after you receive the radiotracer to keep the material from collecting in your bladder.
You must remove jewelry and other metal objects. You may be asked to wear a hospital gown.
Tell your doctor if you are or may be pregnant.
Do not take any medicine with bismuth in it, such as Pepto-Bismol, for 4 days before the test.
There is a small amount of pain when the needle is inserted. During the scan there is no pain. You must remain still during the examination, and you will be instructed when to change positions by the technologist.
You may experience some discomfort due to lying still for a prolonged period of time.
A bone scan is used to:
Test results are considered normal if the radiotracer moves evenly throughout all the bones in your body.
The images should show that the radioactive material has been evenly distributed throughout the body. There should be no areas of increased or decreased distribution. "Hot spots" are areas where there is an increased accumulation of the radioactive material. "Cold spots" are areas that have taken up less of the radioactive material.
If you are pregnant or nursing, the test may be postponed to prevent exposing the developing baby to radiation. If you must have the test while breastfeeding, you should pump and throw away the breast milk for the next 2 days.
The amount of radiation injected into your vein is very small, and nearly all radiation is gone from the body within 2 - 3 days. The radiotracer that is used exposes you to a very small amount of radiation. The risk is probably no greater than with routine or conventional x-rays.
Risks related to the bone radiotracer are rare, but may include:
There is a slight risk of infection or bleeding when the needle is inserted into a vein.
Some abnormalities that may be identified on radionuclide bone scans include:
It is important to understand that bone scan findings must be compared with other imaging studies, in addition to clinical information. You should always discuss the significance of abnormal findings with your health care provider.
Robert E. Coleman, Ingunn Holen, Bone metastases. In: Abeloff MD, Armitage JO, Niederhuber JE, Kastan MB, McKena WG, eds. Clinical Oncology. 4th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2008:chap 57
Baker LH. Bone tumors: primary and metastatic bone lesions. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 212.
Review Date: 11/2/2009
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright ©2010 A.D.A.M., Inc., as modified by University of California San Francisco. Any duplication or distribution of the information contained herein is strictly prohibited.
Information developed by A.D.A.M., Inc. regarding tests and test results may not directly correspond with information provided by UCSF Medical Center. Please discuss with your doctor any questions or concerns you may have.