DEXA scan

A DEXA scan is a medical imaging test used to measure bone density and/or body composition. DEXA is short for dual-energy X-ray absorptiometry.

Why a DEXA scan?

DEXA scans are used to detect conditions such as osteoporosis (bone loss) and sarcopenia (significant loss of muscle mass). Osteoporosis is a condition in which bone mass decreases. This leads to an increased risk of bone fractures. In sarcopenia, muscle mass is lost and problems arise in daily functioning.

DEXA scans are also able to measure the total composition of the body. This provides insight into the amount of body fat and muscle mass. This also makes the test interesting for athletes or people who are overweight and want to know their body fat percentage and muscle mass.

How does a DEXA scan work?

During a DEXA scan, the patient lies on a table while the device sends a low dose of X-rays through the body. The device measures how much radiation the bones and soft tissues of the body absorb (absorb). Not every tissue absorbs the same amount of radiation. In this way, the DEXA scan measures bone density and body composition. These values are then compared with normal values for someone of the same age and sex.

A DEXA scan is a simple and painless test that usually takes less than 15 minutes. The patient does not need to undress and no special preparation is required. To get the best result, the patient must lie still.

It is important to know that DEXA scans are not suitable for everyone. Metal implants, such as artificial joints, can negatively affect the test. The measurement is then not entirely accurate. Also, during pregnancy it is not advisable to have a DEXA scan performed, to avoid exposing the unborn child to X-rays.

Comparison with other imaging techniques

A DEXA scan is the best way to measure bone density. X-rays are less accurate and only show bone loss when bone mass has already decreased severely. In addition, radiation exposure with a DEXA scan is many times lower than with a standard X-ray. CT scans and MRI scans are also less suitable, because they are more expensive and less easily accessible than DEXA scans.