About DEXA Scan
Dual Energy X-ray Absorptiometry (DEXA) is one technique used to measure bone mineral density. Bone mineral density is a test that measures the amount of calcium in a specific region of the bones. From this information, an estimate of the strength of your bones can be made. DEXA uses two different x-ray beams. The amounts of each x-ray beam that are blocked by bone and soft tissue are compared to estimate the bone density. DEXA is the most accurate method for measuring bone mineral density. It is fast and uses very low doses of radiation. DEXA measures bone mineral density on bones of the spine and hip. Under good conditions, DEXA can measure as little as 2% of bone loss per year.
Why is it done
Dexa scan is used to:
- Detect the presence of osteopenia or osteoporosis in a person who has risk factors for developing osteoporosis.
- Detect osteoporosis
- Help determine whether a woman who has gone through menopause may benefit from horone replacement therapy.
- Monitor treatment for osteoporosis.
How to prepare
Dress for comfort. Avoid wearing clothes with metal buttons or buckles for the test. You also may want to leave jewelry at home or remove it for the test.
How is it done
You will lie on your back on a padded table, you can usually wear your own clothes. You may need to lie with your legs straight or with your lower legs resting on a platform built into the table. Testing at least two different bones (preferably the hip and spine) each time is the most reliable way of measuring BMD. It is best to test the same bones and to use the same measurement technique and BMD equipment each time.
How it feels
Usually there is no discomfort during a bond density test. If you have back pain, you may be uncomfortable lying on your back on the flat table.