Bone Mineral Density Scan (DEXA) - What is it for

This procedure measures the patient's bone mineral density (BMD). BMD will tell your doctor whether your bones are brittle or not. Brittle bones mean you will be more susceptible to fractures when you have a fall. For more information on brittle bones or osteoporosis, refer to Osteoporosis, Dept of Endocrinology. In 1963, the first machine to measure bone density used radionuclides. They have since been replaced by machines using X-rays.

Procedure

On the day of the procedure, you should preferably wear loose clothing with no metallic attachments. You might be required to change into a hospital gown. You will be required to answer some simple questions regarding your medical history and medications. There is no injection. You will lie on the imaging couch facing up. A quick scan of your lower spine and your hip bones will be carried out. It should be over in about 25 minutes.

Do I need to make any preparations beforehand?

There is no need to fast.
Patient must not have undergone an X-ray examination with oral contrast within the last 7 days e.g. barium meal as the barium might obscure the lumbar spines.
There should also not be any Nuclear Medicine procedures performed within the previous 2 days. This is to ensure that calculation of the bone mineral density will be accurate.