Bone density scanning, also called dual-energy x-ray absorptiometry (DXA) or bone densitometry, is an enhanced form of x-ray technology that is used to measure bone loss. DXA is today’s established standard for measuring bone mineral density (BMD).
An x-ray (radiograph) is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Imaging with x-rays involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging.
DXA is most often performed on the lower spine and hips. Sometimes the whole body is scanned. Peripheral devices that use x-ray or ultrasound are sometimes used to screen for low bone mass.
When is BMD recommended?
- For a post-menopausal woman.
- Man with clinical conditions associated with bone loss.
- Use medications that are known to cause bone loss, including corticosteroids
- such as Prednisone, various anti-seizure medications such as Dilantin and certain barbiturates, or high-dose thyroid replacement drugs.
- Have Insulin-dependent diabetes, liver disease, kidney disease or a family history of osteoporosis.
- Have high bone turnover, which shows up in the form of excessive collagen in urine samples.
- Have a thyroid condition, such as hyperthyroidism.
- Have a parathyroid condition, such as hyperparathyroidism.
- Have experienced a fracture after only mild trauma.
- Have x-ray evidence of vertebral fracture or other signs of osteoporosis.
What is Osteoporosis?
Osteoporosis literally means ‘porous bones’. It is a disease where the bones in the body become weak and brittle, so much so that they fracture even due to mils stress like bending over, cleaning and coughing. Osteoporosis affects over 6.1 crore Indians- 1 out of 8 men and 1 out of 3 women suffer from osteoporosis, making India one of the largest affected countries in the world.
How does Osteoporosis occur?
The strength of bones depends on the amount of calcium, phosphorous and other minerals that are present in them. Osteoporosis silently depletes the bones of calcium, making them weak and prone to fractures. These fractures occur mostly in the spine, hips and wrists.
Osteoporosis can occur due to several reasons. At menopause, the rate of bone loss in women increases to about 1-3%, thereby increasing their risk of osteoporosis. Bone loss also accelerates in men over 65 years of age. Osteoporosis can also be caused due to endochrinal disorders or from excessive use of certain drugs.
What are the Benefits of BMD Test?
- DXA bone densitometry is a simple, quick and noninvasive procedure.
- No anesthesia is required.
- The amount of radiation used is extremely small.
- DXA bone density testing is the most accurate method available for the diagnosis of osteoporosis and is also considered an accurate estimator of fracture risk.
- DXA equipment is widely available making DXA bone densitometry testing convenient for patients and physicians alike.
What happens during the scan?
There is no special preparation required for the scan. It involves lying on the table, breathing normally. No intravenous injections or oral medication is given. The intensity of radiation is extremely low. The whole procedure takes about 10 to 15 minutes.