DEXA Scan/Bone Density Testing
DEXA scan is a method of Bone Mineral Density Assessment.
Bone Mineral Density Assessment is used to:
Detect the presence of osteoporosis in men and women with particular risk
Screen for osteoporosis, particularly in women
making decisions about hormone replacement therapy at menopause
Predict future fracture risk
Monitor bone density in those with low normal levels and in those with
osteoporosis undergoing treatment
Common uses of this
DEXA scan is used to diagnose osteoporosis on men and
women with the following particular risk factors.
History of bone fracture
A small thin frame
A family history of osteoporosis
Removal of the ovaries
A low calcium diet
Lack of exercise
Certain medicines (such as steroids or anticonvulsants)
Alcohol and tobacco
How does it
Certified medical personnel conducts the exam. The
patient is asked to lie without moving on the scan table but you are able to
breathe normally throughout the procedure. A scanner passes over one area
of your skeleton: your lower spine, wrist or hip. A dual energy beam of low
dose x-rays passes through that area of your body and is measured by a
detector. The scan is repeated for a second skeletal area. DEXA
technology works by measuring the amount of x-rays that are absorbed by the
bones in your body. The two x-ray energies allow the machine to differentiate
between bone and soft tissue, giving an accurate estimation of bone
density. The radiologist produces a report for your physician based on the
bone density measurements and your medical history.
The patient does not feel anything during the procedure.
Even though x-rays are used, the amount absorbed by the patient
is only about 1/10th of that received from a chest x-ray. Other x-ray
procedures have even higher x-ray doses. The x-ray dose from the bone densitometry
test is comparable to the naturally occurring radiation exposed to in one week.
Even though the x-ray
dose for the bone densitometry test is low, inform the operator if you are pregnant or
might be pregnant before your test.
Eat normally on the day of the exam, but avoid calcium
supplements the day of your appointment. If possible, wear a two piece outfit so
you will not need to disrobe entirely and avoid wearing clothing with metal
(buttons, zippers, etc.)