Bone density scanning, also known as bone densitometry or dual-energy x-ray absorptiometry (DXA), is a noninvasive diagnostic procedure used to determine the extent of bone loss by measuring bone mineral density. This procedure is most commonly used to assess the lower spine, forearm and hips, and is considered the current standard for measuring bone mineral density.
Why is it use?
Bone densitometry can help diagnose osteoporosis and monitor its treatment. Bone densitometry is recommended for patients at risk for this disease, as well as bone fractures in general. Certain factors, such as age, body weight, medical history, family history and lifestyle habits, can greatly increase the risk of fractures. Patients at a higher risk for osteoporosis or fractures are often recommended for bone density testing. These may include:
- Post-menopausal women who are not taking estrogen
- Post-menopausal women who are tall (over 5’7) or thin (under 125 pounds)
- Patients with type 1 diabetes, liver disease or kidney disease
- Patients who use medication that cause bone loss, such as corticosteroids or anti-seizure medication Patients with a thyroid or parathyroid condition
- Patients with a high bone turnover Patients who have had nontraumatic fractures or are already diagnosed with osteoporosis
What can I expect?
A bone density scan is a simple, fast procedure with no needles and no need for anesthesia and includes a very small radiation dose. No radiation remains in the body after the procedure, and there are no side effects associated with a bone density scan. This procedure usually takes 10 to 20 minutes to perform, depending on which parts of the body are being examined.
During a bone density scan, the patient lies on a table with an X-ray generator on one side and an imaging device on the other. The targeted area of the body, such as the spine, hip or forearm, will be positioned between the X-ray generator and imaging device. The results of your bone density scan are evaluated and compared to a reference population of similar age, weight and sex. This information is then used to make a diagnosis about your bone status.
How can I prepare?
No special preparation is needed.