DEXA scans are an enhanced form of x-ray used to measure bone loss. These scans are the standard for measuring bone mineral density (BMD). As with x-rays, you expose a small part of your body to a small dose of radiation to produce images of your body. The amount of radiation is very small – less than one-tenth the dose of a standard chest x-ray.
DEXA scans are most often performed on the lower spine and hips. In certain cases in children and older adults, the entire body is scanned. DEXA scans are most frequently used to diagnose osteoporosis, a condition predominately affecting women after menopause. Due to a gradual loss of calcium, osteoporosis involves structural changes causing bones to become thinner, more fragile and more likely to break.
A DEXA scan is an instrumental diagnostic tool for tracking the effectiveness of treatment for osteoporosis as well as for assessing an individual’s risk for developing fractures. Fracture risk is affected by your age, body weight, history of fracture, family history of fractures, cigarette smoking and excessive alcohol consumption.
Bone density testing is recommended if you are
- Post-menopausal and not taking estrogen
- Have a personal or maternal history of hip fractures or smoking
- Post-menopausal and over 5’7” or under 125 lbs
- A man with clinical conditions associated with bone loss
- Use medications known to cause bone loss including corticosteroids like Prednisone or anti-seizure medications like Dilantin
- Have Type 1 Diabetes, liver disease, kidney disease or a family history of osteoporosis
- Have a thyroid or parathyroid condition
- Have x-ray evidence of a vertebral fracture or other signs of osteoporosis
- Have unexplained back pain
- Have lost more than an inch in height
DEXA scans work by sending a thin, invisible beam of low dose x-rays with two distinct energy peaks through you bones being examined. One peak is absorbed predominately by your soft tissue and the other by your bone. The amount absorbed by your soft tissue is subtracted from the total and what remains is your bone mineral density.
The bone density scan takes approximately 30 minutes depending on the body part you need tested. To reduce the possibility of a blurred image, your DEXA scan technician may ask you to hold your breath for a few seconds while the x-ray is being taken.
CLICK HERE to get an appointment checklist for a DEXA Scan