Hello! I’m Dr. Geoffrey Rubin, a radiologist at Duke University in Durham, North Carolina. I’d like to talk to you about bone density scanning. It’s also called dual-energy x-ray absorptiometry but we usually just call it DEXA.
DEXA is a low-dose x-ray exam used to measure bone loss and bone mineral density. It is usually performed on the lower spine and hips to help diagnose osteoporosis, which is a thinning of bone tissue and a loss of bone minerals.
DEXA can track the effects of treatment for osteoporosis and other bone loss conditions and it can assess your risk for developing fractures.
If your doctor has scheduled you for a DEXA scan, there are several things you can do to prepare.
First, you should not take calcium supplements for at least 24 hours before your exam. Tell your doctor if you recently had a barium exam or if you received contrast material for a CT scan. Also, be sure to inform your doctor or technologist if there is any possibility that you might be pregnant.
For the exam, it is best to leave jewelry at home and wear loose, comfortable clothing without metal buttons or zippers. You may be asked to wear a gown. You will either lie on a table or place your arm, foot or hand in a small device that is on the table. You will be asked to lay very still and hold your breath briefly while the x-ray machine captures the images.
While there is a slight chance of cancer from excessive exposure to radiation, the amount of radiation used in a DEXA scan is extremely small and the benefit of an accurate diagnosis far outweighs the risk. Radiation does not remain in your body after an x-ray exam.
Overall, DEXA is a simple, quick and noninvasive test. It is the most accurate method available for the diagnosis of osteoporosis and an accurate method for estimating the risk of fracture.
I hope that this information is helpful to you. To learn more about DEXA, visit us at RadiologyInfo.org.