Bone density testing is performed by a radiologist and uses a scanner that moves over your body. The scanner uses low dose X-rays to produce images of your bones. These images are displayed on a computer screen. The procedure requires you to be very still, and you may be asked to hold your breath. The bone density scan will determine the density of bones in various parts of your body, such as the hips, forearms, and hands.
You should have your bone density test performed at least once every two years. However, your doctor may order repeat tests if you notice a significant change in your bone density. Follow-ups may also be necessary if you’re taking high doses of steroid medication. After the test, the radiologist will analyze the images and will send a report to your primary care physician. The referring physician will discuss the results with you.
Dual-energy X-ray absorptiometry (DXA) is the most accurate way to measure bone density. It uses two different X-ray beams and compares the amounts of each beam that is blocked by bone with the amounts of light absorbed by soft tissue. It is highly accurate and can detect bone density losses of up to 2% per year. This type of test is fast, noninvasive, and produces accurate results with minimal radiation.
The test is performed in a doctor’s office and requires the patient to lie on a padded table. The patient may need to remain in this position for the entire time, and may also be asked to rest their legs on a padded platform. This is done using low-dose X-rays. The images are then sent to an expert who reads them. Results may take a few days to receive, depending on the doctor’s office. The results are usually reported in g/cm2 and T-score format, and are compared to a reference population.