Bone Density Test

An example of the DEXA bone densitometry readout

A DEXA bone densitometry test is used to aid in the diagnosis of osteoporosis and other conditions that cause bone loss.

It is also a very useful tool for evaluating the effects that treatment has had on those conditions.

Just as in a common x-ray, a bone density scan is a painless medical test that physicians use for the diagnosis and treatment of various conditions, such as osteoporosis. The test involves exposing the part of the body being examined to a small amount of ionizing radiation to form pictures of the body. Two beams are fired into the body, one measuring soft tissue and the other measuring bone. The difference between the two readings determines bone density.




What to Expect

How Does the Procedure Work?

Specialized DEXA technology has software that calculates and displays bone density measurements on a computer monitor. It makes its calculations by sending a thin invisible beam of low-dose x-rays with two energy peaks through the bones and soft tissue. One peak is absorbed and measures the soft tissue and the other measures the bone. The soft tissue is subtracted from the total of the two combined and what remains is the patient’s body mineral density.

Why Did my Doctor Order This Test?

Your Physician May Order a Bone Density Test If:

  • you have had x-rays showing a vertebral fracture
  • you have been diagnosed with osteoporosis
  • you are a post-menopausal woman, not on estrogen therapy
  • you are a post-menopausal woman who is 5 feet 7 inches or less and weighs less than 125 pounds
  • you have a personal or family history of smoking or hip fracture.
  • you have a thyroid or parathyroid condition
  • you have type 1 diabetes, kidney disease, or liver disease
  • you are a man with medical conditions known to cause bone loss
  • you have high levels of collagen in urine specimens

How Long Does the Procedure Take?

Depending on the parts of the body being examined the bone density test typically takes 10 to 30 minutes.

  • Bone Density Study
  • Osteoporosis Scan
  • Lateral Vertebral Assessment
  • Body Composition

How to Prepare

Women should always tell their x-ray technologist or physician if there is a possibility of pregnancy. If you have had barium, CT scan, radioisotope, or if you have been injected with any contrast dye used for testing purposes please call our offices. You may be required to wait 10 – 14 days before your bone density procedure. Do not take calcium supplements for a minimum of 24 hours before your scheduled test. Wear comfortable clothing that is free of any metal objects and that is easy to change if you are asked to wear a gown. You may be asked to remove any jewelry as well as your eyeglasses before your exam.

Equipment Used for This Procedure

Hologic Discovery DXA Machine

The Hologic Discovery DXA Machine is used in determining bone density, and can also help find calcified plaques in the abdominal aorta (which can be an indicator of heart disease or stroke). With enhanced speed and image quality, this machine can provide exams in as little as ten seconds.