FDA Approves Use of APL-Developed Bone Density Technology

The Food and Drug Administration has granted 510K marketing clearance for the incorporation of bone health analysis software developed by The Johns Hopkins University Applied Physics Laboratory (APL), in Laurel, Md., for use in a commercially developed bone scanner.

Dual-energy x-ray (DXA) scans are the most widely-used method for measuring bone mass and diagnosing osteoporosis, but they can not directly measure mechanical strength. The APL-developed Hip Structure Analysis (HSA™) technology uses conventional DXA images of the geometric properties of bone to determine strength.

In February, APL signed an agreement with Hologic, Inc., a leading provider of diagnostic imaging and state-of-the-art digital imaging systems directed towards women's health, granting it exclusive, worldwide rights to the HSA technology. FDA's approval clears the way for Hologic to market its DXA bone densitometers, which will rely heavily on APL's HSA technology to help doctors determine if a patient's bones have been weakened and treatment is required.

HSA represents a significant advance in imaging bone structure, and Hologic intends to initially use it in bone research. "In studies, HSA may help researchers understand how the femur weakens with age and how pharmaceutical treatments work to reduce fracture risk at the hip," says Brad Herrington, Hologic vice president of Skeletal Health Imaging.

APL's Pursuit of Advanced Scanning Techniques

"FDA's 510K approval is a major milestone in APL's quest to make the next generation of DXA techniques a reality and provide significant benefit to society as a whole," says APL's Dr. Harry K. Charles, Jr., who is part of the team responsible for the HSA software. Further, he adds, "it is yet another example of APL's ability to address problems of significant national concern while providing practical technology solutions that attract industrial partners through technology transfer."

The development of HSA is an outgrowth of the Lab's work on the Advanced Multiple-Projection Dual-energy X-ray Absorptiometry (AMPDXA) project to design, build, and test a precision, three-dimensional scanner system for monitoring the harmful effects of weightlessness on the human musculoskeletal system during prolonged spaceflight.

The AMPDXA project was funded for more than six years by the National Space Biomedical Research Institute (NSBRI). Charles explains that this partnership with the NSBRI, while ending this year due to changes in the national space program priorities, fostered significant advancements in the monitoring of bone health and complications arising from osteoporosis, including the development of the HSA software.

Charles — along with HSA pioneer Thomas J. Beck of the JHU School of Medicine — will continue to fine-tune the HSA and DXA technology. "The current scanning technology is very advanced over what's commercially available," Charles says. "But it uses a two-dimensional radiographic approach to a three-dimensional skeleton, and what doctors really need is three-dimensional images."

HSA™ is a trademark of The Johns Hopkins University Applied Physics Laboratory.