The Bone Densitometry or DEXA Scan

What is a DEXA or Bone Densitometry scan?

• DEXA (bone densitometry) stands for ‘dual energy X-ray absorptiometry’
• It's a very simple examination where you lie on a special bed while the arm of a scanner passes over you
• The bone densitometer measures your bone mineral density (BMD)
• It will compare your measurements to those of other people of a similar age and weight, and of the same sex and ethnic background
• Your doctor will use this information to decide if you have osteoporosis and if you're at risk of having brittle bones
• Before the introduction of this kind of dedicated equipment, evaluating bone density using conventional x-ray systems didn't reveal a potential problem until a patient had lost 25 to 30 percent of the bone density
• Now, with short scanning times and low x-ray doses, this highly sensitive equipment can help identify risk at a much earlier stage. In addition, it can also evaluate your response to treatment, helping to prove that the chosen therapy is effective

What is osteoporosis?

• Osteoporosis is the depletion of bone mineral density
• It affects almost half of all post-menopausal women (the highest risk group for the condition) and causes progressive bone loss which in turn increases the risk of fracture
• If your doctor decides that you have osteoporosis, potential changes in diet, exercise habits and/or medication can help prevent further deterioration of the bone

Is a bone-density scan the same as a DEXA scan?

• No. The two procedures sound similar but they're very different and are used for different purposes. A bone scan is a medicine study (which uses injections of an isotope) to look for cancer, stress fractures, and other bone or joint problems. It doesn't measure bone density and isn't used to diagnose osteoporosis

Who will I see?

• A small team of radiography staff will look after you during your visit and one of the radiographers will carry out the scan

Is it safe?

• The DEXA examination involves a very small dose of radiation
• However, please bear in mind that a bone-density scan of your spine has a much smaller dose of radiation than a chest X-ray and is typically equivalent to the amount you'd expect to receive on a long aeroplane flight

Do I need an injection?

• No, you'll not need an injection

Before the scan

• Unless we let you know, you don't need to make any special preparations for your DEXA examination and you can continue to eat and drink as normal and take any prescribed medicine
• Please let us know about any special needs you have - for example, if you need wheelchair access, you're hard of hearing or you have poor eyesight

What happens during my appointment?

• When you arrive you should go to the reception desk - please bring your appointment letter which may have details of who to ask for
• The radiographer or another member of staff will meet you and explain the procedure to you
• You should wear comfortable clothes that have no metal zips or buttons. Or, we can provide you with a gown to change into. If you wear a bra we'll ask you to take it off
• We'll take you into the scanning room and ask you to lie down on the scanner table (couch)
• The arm of the scanner will pass over you

Will it be uncomfortable?

• There is no discomfort during your scan

After the scan

• You can eat and drink normally after the scan
• You can drive home afterwards and return to work if you need to

How long will it take?

• Spine or hip measurements take around five minutes. You should allow an hour from the time you arrive for your appointment to the time that you leave

Are there any side effects?

• There are no known side effects from a DEXA scan

When will I get the results?

• We'll send the results to your doctor or consultant who'll be able to discuss them with you at your follow-up appointment

Can I bring a relative or friend?

• Yes, but they'll only be allowed to go into the examination room in special circumstances (for safety reasons)
• Children aren't allowed into the room while you're having the scan, so you'll need to make arrangements for them before your appointment

Learn more

• AMTV: Patient Channel - browse our patient video gallery here
• Scan Dictionary - an A-Z of common terms
• Find your location - find your location here
• Arrange a scan - if you'd like to arrange a scan for yourself, find out more here
• Infection control - learn what we're doing to keep you safe here
• Got a question, query or concern? Just contact us, we'd be delighted to help