What Is a DEXA Scan and Who Is It Safe For?

A dual-energy X-ray absorptiometry (DEXA) scan is an imaging take a look at that measures the quantity of calcium and different minerals in your bones. The measurement signifies bone density, which is bone energy and thickness.

A DEXA scan is most ceaselessly used as a screening instrument for osteoporosis, a situation that makes your bones brittle and weak. You may also hear a DEXA scan known as a DXA scan, bone mineral density scan, or bone densitometry.

A DEXA scan can diagnose osteopenia and osteoporosis and predict your danger of future fractures. In case you’ve already been identified with osteoporosis, the scan can verify in case your bone density reveals adjustments in response to therapy.

You might have osteopenia in case your bones are thinning greater than is typical on your age. Along with ageing, household historical past, poor bone mass growth in youthful years, and sure medicines and circumstances can put you in danger for osteopenia. Osteopenia additionally places you in danger for osteoporosis, which will increase your danger of fracture.

As a result of the danger for fracture in osteoporosis is highest on the hips, backbone, and wrist, a DEXA scan will often measure these bones. It might probably additionally measure the fats and muscle composition in particular components of the physique, together with the arms, legs, and pelvis.

Who Wants a DEXA Scan?

Due to the elevated danger of osteoporosis and fracture, a DEXA scan is often beneficial for girls older than 65 and males older than 70. Girls who’re youthful than 65 however who’re at increased danger for osteoporosis may also want a DEXA scan. Chances are you’ll be in danger for osteoporosis at a youthful age when you have:

Estrogen deficiency
Low physique mass (lower than 127 kilos)
A mom who fractured her hip at any age
No interval for over a 12 months earlier than you’re 42

Girls youthful than 65 and males youthful than 70 might also want a DEXA scan in the event that they smoke, have gotten shorter, or have skilled a extreme curving of the higher backbone (thoracic kyphosis).

DEXA screening can be beneficial for anybody taking medicines that will have an effect on their bone mineral density. These medicines embrace anticonvulsants and continual heparin, an anticoagulant.

Some circumstances, together with rheumatoid arthritis, hyperthyroidism, and Cushing’s illness, might also negatively have an effect on bone mineral density. See in the event you ought to get screened for bone mineral density loss when you have a situation that may impression your bone energy.

As a result of a DEXA scan will also be used to measure physique mass and physique fats, a healthcare supplier might order a DEXA scan when you have:

Most cancers
Consuming problems
Malabsorption—the physique’s lack of ability to correctly take in vitamins

The DEXA scan makes use of low-energy X-rays of various power ranges to measure bone density. In comparison with the opposite scans accessible for the screening of your bone well being, a DEXA scan is comparatively cheap and has a shorter scan time.

Earlier than the Take a look at

Earlier than the scan, a health care provider might measure your weight and top. For the scan, you can be requested to both lie on the padded scanner desk or sit upright subsequent to the desk. If you’re mendacity down, your legs will both be straight out or resting on a padded field. Your foot may also go in a tool to show your hip inward.

Throughout the Take a look at

The desk has an instrument above and beneath the desk that makes a big C-shape. Two scanning machines work concurrently to take photos of whichever physique half a healthcare supplier requested assessments. As well as, if you’re getting a DEXA scan to measure your fats and muscle composition, the machine will scan your whole physique.

The healthcare supplier might ask you to carry your breath for just a few seconds throughout the scan. It is vital to remain nonetheless whereas the scanner is taking the photographs. The take a look at often takes 15-20 minutes.

After the Take a look at

The photographs are despatched to the technician’s pc, which a healthcare supplier later views. Your supplier will comply with up along with your scan outcomes and suggestions for any therapy or additional testing which may be wanted.

DEXA scans are typically thought of secure. The radiation publicity is small and akin to the background radiation of on a regular basis life.

Though the radiation publicity is small, the take a look at isn’t beneficial for people who find themselves pregnant. That’s as a result of even low doses of radiation will be harmful for an unborn child. Speak with a healthcare supplier if you’re pregnant or assume you could be pregnant.

The scan additionally barely will increase the potential for most cancers sooner or later. Whereas everyone seems to be uncovered to some sorts of radiation in each day life, any extra publicity—reminiscent of by an imaging take a look at—can marginally improve most cancers danger. The elevated danger is much like that of an everyday X-ray. Speak to a healthcare supplier to weigh the danger of radiation publicity and the advantages of a DEXA scan.  

A healthcare supplier might ask you to cease any calcium dietary supplements 24-48 hours earlier than the scan. You must also keep away from sporting steel jewellery or clothes with steel on it.

People who find themselves pregnant or assume they could be pregnant ought to speak to their healthcare supplier earlier than going for a scan. If in case you have not but gone by menopause, you will be requested if there’s any risk that you just could be pregnant. You might also be requested to provide a urine pattern so the power can ensure you aren’t pregnant earlier than administering the X-ray.

A healthcare supplier might ask you to carry the outcomes of any earlier scan. They will wish to study the adjustments in your bone mineral density between the assessments.

The outcomes of the DEXA scan often fall into two scoring programs: the T-score and Z-score. These scores assist healthcare suppliers study extra about bone mineral density and bone well being.

Within the T-score, your bone mineral density is in comparison with that of a wholesome 30-year-old. Within the Z-score, your outcomes are in comparison with the bone mineral density of individuals of the identical age, intercourse, and race.

Decoding Your Outcomes

With each T- and the Z-scores, the decrease the quantity, the thinner your bones—and the upper your danger for fracture. The next T-scores can point out regular or higher-than-normal bone loss:

Regular bone density: -1.0 or aboveOsteopenia: Between -1 and -2.5Osteoporosis: Under -2.5