The iDXA system.
Image courtesy of GE Healthcare,

Special report: Densitometry

August 30, 2013
by Nancy Ryerson, Staff Writer
People who want to know their body’s breakdown of fat, muscle and bone have a few options. They can strip down to a bathing suit and submerge themselves in a weighing tank, then hold their breath for the proper amount of time or risk starting the process all over again. If that doesn’t tickle their fancy, they can be pinched by skin calipers. Or they can stand in Bod Pods, futuristic looking capsules that take measurements based on air displacement.

But there’s a newcomer on the body composition scene, in the form of a piece of equipment that’s been under physicians’ noses for years: bone densitometers, or DXA scanners. More and more imaging centers and health clubs are using the modality traditionally reserved for bone density screenings to produce body composition studies.

The scan provides details of the fat content of the entire body, including the fat in places tools like calipers miss, like around organs, as well as muscle and bone mass. As a bonus, subjects don’t have to shuck clothing (minus metal zippers), and the scan only takes around six minutes. Plus, the specifics it offers puts it head and shoulders (and arms) above other methods.

“If a person gets a scan then comes in three months later, we can tell you, you’re down 2.1 pounds of fat in your left arm,” said Dr. David Parker, executive director at the Washington Institute of Sports Management in Kirkland, Wash.

The institute’s reports give visitors feedback that includes information on their body fat percentage, ideal fat percentage, ideal weight and target caloric intake. A single scan costs $125 out-of-pocket.

Body composition studies are breathing new life into a modality losing some of its popularity thanks to low reimbursements for bone density scans. With the country more focused than ever on soaring obesity rates and malnutrition, body composition studies are throwing DXA a much-needed bone.

Weight concerns offer an expanding role

While DXA scanners have always had the ability to do body composition studies, it has only been within the last year or so that OEMs have heard about them being used that way more often.

“What we’re finding is that a lot of people have concentrated on bone density, so as reimbursements and some other business has fallen off for them, they’ve found that by using body comp, they’re getting more utilization out of their systems,” says Michael Kelly, business leader for GE Lunar bone densitometers.

Kelly says that using DXA for body composition is still in early adoption, but that it’s taken off with professional sports teams, who use it to individualize and customize training for athletes.

“I would say that’s probably going to continue to expand and get more into colleges, and more into health spas and gyms and those kinds of institutions,” says Kelly.

GE and Hologic, the two leaders in the bone densitometer market, have both released software updates to correspond with the newfound interest in body comp studies.

GE’s software release, Encore Version 14, includes measurement capability for visceral fat. Its upcoming Version 15 release will add simplified reporting structures and simplified options, Kelly says.

In 2011, Hologic incorporated National Health and Nutrition Examination Survey whole body reference data into its Discovery line of DXA systems for use with body composition studies.

This July, Hologic announced its newest release, its first top-down update of its bone densitometers since 2002. It’s called Horizon and includes an extremely low noise detector, ideal for scanning obese patients.

“Horizon yields better image quality on obese patients, whether for body composition or typical bone density evaluations,” says John Jenkins, vice president of marketing at Hologic. He says the majority of customers he hears from are interested in providing body composition studies at their centers.

Body comp bull’s eye
Parker of the Washington Institute has been involved in body composition studies since the 1970s. He’s watched curious patients take the plunge in hydratic weighing around 10,000 times, and helped invent the original Bod Pod.

He says while those methods can be useful, factors like how much air is in your lungs can skew results. The Washington Institute of Sports Medicine introduced DXA body composition scans two years ago, and the center is now the largest in the area.

Body comp DXA scans today are often considered the “gold standard” for accuracy, though adjustments and calculations still need to be made after the scan.

“I’ve heard people say the only way to be more accurate than a DXA is to wait until the person dies to chop up the body and weigh the pieces,” says Dr. Dan Stickler, founder of Synchronicity Wellness in Asheville, N.C., a center that has been using DXA body comp scans as the basis for its health plans since 2005. He says software updates over the years have made the scans increasingly accurate.

“When I look at someone, I can generally tell what their body comp is going to be,” says Stickler, who was a bariatric surgeon before becoming interested in alternative weight loss programs. “DXA matches what I know, while the other methods usually don’t.”

No bones about it?
The need for a complete understanding of body composition is one possible reason the scans have not yet become widespread in imaging centers rather than wellness centers. While Stickler can guess a person’s body composition with the naked eye, many radiologists may not be as familiar with the process or the readouts the software creates.

But because body composition scans are paid for out-of-pocket, they can become an additional source of revenue for imaging centers that’s relatively easy to incorporate. As all DXA scanners can perform body composition studies, there’s no special hardware or software required — facilities just need someone who can decipher the scans.

“You need someone working within your office that’s an expert at body composition so that then they can interpret the results for the patients in a way that they’ll understand, so it’s not just data being shoved at you,” says Parker. He notes that results are provided in the metric system, so his team converts the data for his American customers.

Parker says he hopes future readouts will include more consumer-friendly formatting.

Because DXA scanners are not specifically designed for body composition, Parker has found a few additional changes he hopes to see incorporated into future designs. He says the table can’t accommodate some larger patients, as it fits a height of up to six-foot-four and 450 pounds.

Additionally, as stated earlier, body comp scans are not covered by insurance, posing another challenge to introducing the scans into a practice.

“You can be 500 pounds and dying of heart disease, or dying of anorexia, and they will not pay for a DXA,” says Parker. “The business model isn’t built on making money.”

When Parker decided to invest in Hologic scanners, he says he discussed with the company how to make its bottom line work while providing almost exclusively body comp studies rather than bone density scans. He’s been successful, but his kind of center seems to be a rarity. Currently, the Washington Institute of Sports Management is the only Hologic “center of excellence” for body comp.

Diversifying DXA
Despite potential challenges in providing scans outside of dedicated centers and health clubs, the tool holds potential for a wide range of patient populations.

“I think that DXA is probably the clinical gold standard for body composition assessment, and there are three really good uses for that today,” says Dr. Neil Binkley, co-director of the Osteoporosis Clinical Center & Research Program at the University of Wisconsin. “The first is obesity and management of obesity. The second is sports performance, and the third, is sarcopenia, the age related loss of muscle mass and muscle function that happens to us as we get older.”
At the Washington Institute of Sports Management, Parker says 35 to 40 percent of his visitors are athletes, 50 percent are overweight and 5 percent have been referred by doctors to track recovery from anorexia. Synchronicity Wellness often works with older former athletes looking to get back in shape.

In the future, GE’s Kelly predicts body composition studies will be used in conjunction with the bone density information traditionally gathered by DXA scans on certain at-risk populations.

“Even in the U.S., a lot of children go to bed hungry every night, so there’s a lot of malnutrition in this country, and that affects bone health also,” says Kelly. “I think we’re starting to see a trend also towards more scanning and looking at younger and younger patients. We’re starting to really understand the way we eat now, and the way we exercise now, and the impact that’s had on bone health.”

He believes DXA can also play a role in preventing diseases that contribute to the cost of health care.

“More and more, we’re starting to understand where fat is in the body, and the impact that has on diabetes and other disease,” says Kelly. “I think what we’ll see is that as people become more aware of the impact obesity has on their body and their disease state, and as they become more focused on what they can do about that, this will be a primary tool for people to really understand their body composition and how to eat and exercise differently.”

DOTmed Registered Bone Densitometers - July 2013 Companies

Names in boldface are Premium Listings.
Jerry McLaughlin, DataStream Medical Imaging Systems, Inc., CA
Moshe Alkalay, Hi Tech Int'l Group, FL
DOTmed Certified
David Denholtz, Integrity Medical Systems, Inc., FL
DOTmed Certified
DOTmed 100
Jeff Rubinoff, Complete Medical Services, MI
DOTmed 100
Alison Fortin, Global Inventory Management, NH
DOTmed Certified
DOTmed 100
Ben Williams, DEXA Solutions, LLC, WI
Joseph Shafe, Assured Imaging, AZ
John Pereira, United Medical Technologies, FL
DOTmed Certified
DOTmed 100
Ian Alpert, Tandem Medical Equipment, NY
DOTmed Certified
DOTmed 100
Robert Serros, Amber Diagnostics, FL
DOTmed 100
Jaime Munoz, Jaco Medical Equipment, Inc, CA
DOTmed 100
Steve Powner, Best Used Medical Equipment, GA
Alan Keim, Lone Oak Medical Technologies, PA
Omar D. Rodriguez, Professional Medical Equipment, TX