Purpose, Preparation, Risks, and Results

A dual-energy X-ray absorptiometry (DEXA) scan is an imaging check 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 tool for osteoporosis, a situation that makes your bones brittle and weak. You may additionally 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 recognized with osteoporosis, the scan can test in case your bone density exhibits modifications in response to remedy.

You will have osteopenia in case your bones are thinning greater than is typical to your age. Along with getting older, household historical past, poor bone mass growth in youthful years, and sure drugs and situations can put you in danger for osteopenia. Osteopenia additionally places you in danger for osteoporosis, which will increase your risk of fracture.

As a result of the chance for fracture in osteoporosis is highest on the hips, backbone, and wrist, a DEXA scan will normally measure these bones. It may well 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 normally really helpful for ladies older than 65 and males older than 70. Girls who’re youthful than 65 however who’re at greater danger for osteoporosis may also want a DEXA scan. You could be in danger for osteoporosis at a youthful age in case 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 may 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 also be really helpful for anybody taking medicines which will have an effect on their bone mineral density. These drugs embody anticonvulsants and continual heparin, an anticoagulant.

Some situations, together with rheumatoid arthritis, hyperthyroidism, and Cushing’s disease, may negatively have an effect on bone mineral density. See if you happen to ought to get screened for bone mineral density loss in case you have a situation that may impression your bone energy.

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

• Most cancers
• Eating disorders
• Malabsorption—the physique’s incapability to correctly soak up vitamins

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

Earlier than the Check

Earlier than the scan, a physician might measure your weight and peak. 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.

In the course of the Check

The desk has an instrument above and under the desk that makes a big C-shape. Two scanning machines work concurrently to take photographs 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 essential to remain nonetheless whereas the scanner is taking the photographs. The check normally takes 15-20 minutes.

After the Check

The pictures are despatched to the technician’s laptop, which a healthcare supplier later views. Your supplier will observe up along with your scan outcomes and proposals for any remedy or additional testing that could be wanted.

DEXA scans are usually thought-about protected. The radiation publicity is small and similar to the background radiation of on a regular basis life.

Though the radiation publicity is small, the check shouldn’t be really helpful for people who find themselves pregnant. That’s as a result of even low doses of radiation might be harmful for an unborn child. Speak with a healthcare supplier if you’re pregnant or suppose you is likely to be pregnant.

The scan additionally barely will increase the opportunity of most cancers sooner or later. Whereas everyone seems to be uncovered to some sorts of radiation in each day life, any further publicity—corresponding to by means of an imaging check—can marginally enhance most cancers danger. The elevated danger is just like that of a daily X-ray. Speak to a healthcare supplier to weigh the chance 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 metallic jewellery or clothes with metallic on it.

People who find themselves pregnant or suppose they is likely to be pregnant ought to discuss to their healthcare supplier earlier than going for a scan. When you’ve got not but gone by means of menopause, you will be requested if there may be any chance that you just is likely to be pregnant. You may additionally be requested to provide a urine pattern so the ability can ensure you aren’t pregnant earlier than administering the X-ray.

A healthcare supplier might ask you to convey the outcomes of any earlier scan. They’re going to need to study the modifications in your bone mineral density between the assessments.

The outcomes of the DEXA scan normally fall into two scoring methods: 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 above
• Osteopenia: Between -1 and -2.5
• Osteoporosis: Beneath -2.5