Bone Density Scan

About Bone Density Scan (DEXA)

Bone density scanning, also called bone densitometry is an enhanced form of x-ray technology that is used to measure bone loss. DEXA is today’s established standard for measuring bone mineral density (BMD). DEXA is most often performed on the lower spine and hips. Portable devices including some that use ultrasound waves rather than x-rays, measure the wrist, fingers or heel and are used for screening purposes.

What are some common uses of the procedure?

DEXA bone densitometry is most often used to diagnose osteoporosis, a condition that often affects women after menopause but may also be found in men. Osteoporosis involves a gradual loss of calcium, causing the bones to become thinner, more fragile and more likely to break. DEXA is also effective in tracking the effects of treatment for osteoporosis and other conditions that cause bone loss. The DEXA test can also assess an individual’s risk for developing fractures.

How is the procedure performed?

This examination is usually done on an outpatient basis. In the Central DEXA examination, which measures bone density in the hip and spine, the patient lies on a padded table. An x-ray generator is located below the patient and an imaging device, or detector, is positioned above. To assess the spine and hips the patient’s feet are placed in a brace that rotates the hip inward. The detector is then slowly over the area generating images on a computer monitor. The DEXA bone density test is usually completed within 10-30 minutes.

Are there any preparations?

On the day of the exam you may eat normally. You should not take calcium supplements for at least 24 hours before your exam. You should wear loose, comfortable clothing, avoiding garments that have zippers, belts or buttons made of metal. You may be asked to remove some or all of your clothes and wear a gown during the exam. Inform the technologist if you recently had a barium study or have been injected with a contrast material for a CT scan. You may have to wait 10-14 days before undergoing a DEXA test.

Bone density testing is strongly recommended if you:

• Are a post menopausal women and not taking estrogen.
• Have a personal or maternal history of hip fracture.
• If you are a smoker.
• Are a post menopausal woman who is tall (over 5 feet 7 inches) or thin (less than 125 pounds).
• Are a man with clinical conditions associated with bone loss.
• Use medications that are associated wit hbone loss, including corticosteroids such as Prednisone, various anti-seizure medications such as Dilantin and certain barbiturates, or high thyroid replacement drugs.
• Have type 1 diabetes, liver disease, kidney disease or a family history of osteoporosis.
• Have a thyroid condition such as hyperthyroidism.
• Have experienced a fracture after only mild trauma.
• Have had x-ray evidence of vertebral fracture or other signs of osteoporosis.

When will I know the results?

A radiologist, a physician specifically trained to supervise and interpret radiology examinations, will analyze the images and send a signed report to your primary care or referring physician, who will share the results with you.

Questions or concerns?

If you have any questions concerning your imaging procedure , please call St. Joseph Medical Center Department of Radiology – 610-378-2232.