bone-composition

Body Composition Dexa Scan


Body composition analysis, also known as a DXA or dexa scan, provides information about your bone density, body fat, and muscle mass, and is helpful when evaluating levels of physical fitness. The term “dexa” stands for dual-energy X-ray absorptiometry, a technology and uses two low-energy X-ray beams for assessing body composition and bone density.

Dexa Scan Body Fat Analysis

Dexa body composition analysis also delivers precise measurements of segmental body fat distribution in regions such as the arms, legs, waist (android), hips (gynoid), and trunk (torso). Dexa scans list body fat statistics comprised of two types of fat, visceral (abdominal) and subcutaneous.

Subcutaneous fat is the kind you can grasp with your hand; whereas visceral fat lies deep within your abdominal cavity, around organs like your heart or liver. Dexa scans do not provide an analysis of visceral fat, but they can be valuable for patients and athletes continually trying to improve their overall health and physique.

Physicians concerned about health conditions related to visceral accumulation such as a fatty liver will likely refer their patient for another form of medical imaging such as MRI, CT, or shear-wave elastography ultrasound.

DEXA Scans for Weight Loss and Training

Insight Medical Imaging provides body composition analysis at 11 clinics in Edmonton as well as Fort McMurray. These scans are beneficial for athletes with health and fitness goals who are searching for the most accurate tracking system to monitor their progress.

Dexa body composition scans help establish a starting point and a target for athletes in pursuit of a specific goal. As GE Healthcare states, “for highly trained athletes, even a small change in body composition can significantly affect performance. Body composition monitoring provides valuable information that athletes and their trainers can use to adjust diet and training regimens.”

While many patients with weight loss goals tend to focus on body fat percentage, dexa scans provide additional value by breaking the tissue down into fat, muscle, and mineral in your bones. These scans offer a more complete and accurate assessment compared to one-dimensional anthropometric exams like body mass index (BMI), bioimpedance, bod-pod measurements, and hydrostatic weighing.

The Three Types of Tissue Measured by a Dexa Scan Include:

  1. Body fat
  2. Mineral in your bones
  3. Lean tissue such as organs and muscles

Dexa Scan Results

When you have your dexa body composition analysis performed at Insight Medical Imaging, your test results will provide both summary statistics as well as an enhanced composition analysis.

Summary Statistics

The summary statistics will provide you with tissue (% fat) in relation to your age and what percentile you fit in based on historical averages. Our reports also include total body tissue quantitation and total bone density representations highlighting your skeletal structure, lean tissue, and fat.

The images clearly outline your body composition with colour-coding, indicating where fat percentages may vary. For example, your legs may have more yellow around the outside, showing a higher fat percentage in your calves than in your forearms.

T-score and Z-score Meaning

The summary statistics also state your bone mineral density (BMD) score in relation to age and a corresponding young adult (YA) T-score. The YA T-score represents how many standard deviations a patient’s bone density differs by when compared to the average young adult.

Reports at Insight Medical Imaging also specify an age-matched Z-score, which shows how many standard deviations a patient’s density differs by when compared to a larger sample size of the same age. These scores are outlines on a densitometry reference graph and range from +2.0 to -5.0.

Enhanced Composition Analysis Breakdown

The enhanced composition section breaks down your total body mass by region, including arms, legs, trunk (left and right), android, and gynoid. The analysis calculates total mass and tissue fat (%) for each area and the data is further segmented into fat, lean tissue, and bone mineral content (measured in grams).

What Happens During my Dexa Scan?

  • At the time of booking, you will be asked to wear clothing that does not contain any metal (snaps, buttons, zippers) for your appointment. If you forget on the day of your exam, you may be asked to change into a gown when you arrive; we do not want any metal on your clothing.
  • You will be weighed and your height measured before your scan.
    • Our scanning beds have a maximum weight restriction of 300 pounds.
  • You will be positioned on a bed by our technologist. The scan should take approximately 10 minutes. Please remain as still as possible for your scan, as movement may blur the exam images.
  • Using dexa or dual-energy X-ray absorptiometry, we will calculate your body composition.
    • If there is any chance that you are pregnant, please talk to your doctor before coming in for your body composition.
  • A small scanner will pass over you, measuring the three types of body tissue previously mentioned.
  • After the dexa scan is complete, one of our radiologists will review the results and send a detailed report to your doctor and yourself. We try our best to send the results as soon as possible, usually within one business day.

What if I Have a Prosthetic Hip or Knee?

Before we begin the scan, a technologist will confirm that you have no metal present on your clothing. This precaution is to enhance image quality and clarity as much as possible. Therefore, it is natural for patients with a prosthetic hip or knee to assume they are ineligible for a dexa scan.

While trace metals in an artificial joint may have some impact on dexa accuracy overall, the effect on body fat analysis is usually negligible. Thus, patients with prosthetic hips or artificial joints can still benefit from a body composition scan.

Important Notes

  • All DEXA scans, such as body composition analysis, use ionizing radiation. Therefore, there must be zero chance a patient is pregnant for their scan. We ask all females between 11 and 55 years about their last menstrual period to determine the possibility of pregnancy.
    • We ask this personal question to protect a potential fetus from radiation exposure; please do not be offended. If there is any chance you are pregnant, please tell your doctor before coming to your DEXA scan.
  • You must have a doctor’s referral for this exam since the exam involves exposure to a low dose of radiation. Therefore, please remember to bring your doctor’s referral, photo ID, and Alberta Health Care card with you to your appointment.

Orientation

Our technologist will help position you on a bed, where you will lie flat on your back.

Cost

Alberta Health care does not cover this exam. The cost for a dexa body composition analysis scan is $60.

Duration

Dexa body composition analysis scans typically take 10 minutes to complete. The most significant factor impacting the duration for a dexa scan is patient mobility.

Exam Preparation

Planning your next appointment? Learn more about body composition analysis exam preparation and find the clinic most convenient for you.