Feb 20 2009
The fight against bone disorders that affect millions of Americans will soon receive a boost from an ultrasound device being developed by space biomedical researchers.
The technology under development will allow early prediction of bone disorders such as osteoporosis and guided acceleration of fracture healing.
National Space Biomedical Research Institute (NSBRI) scientists are developing the technology to assist astronauts during long-duration spaceflights. Like the elderly on Earth, astronauts in space lose bone structure and quality.
Dr. Yi-Xian Qin, associate team leader for NSBRI's Smart Medical Systems and Technology Team, calls the new technology Scanning Confocal Acoustic Navigation (SCAN). He said the objective is to develop a small, mobile device that is easy to use and patient friendly.
"SCAN uses non-invasive and non-destructive ultrasound to image bone. It will allow us to identify weak regions, to make a diagnosis and to assist in healing fractures," said Qin, who is also the director of the Orthopedic Bioengineering Research Laboratory at Stony Brook University - State University of New York.
Stress-related fractures are a big concern for astronauts during long missions to the moon or in space. Qin said the fracture rate could be high on the moon due to workload force, heavy spacesuits and gravity that is one-sixth of Earth's.
The researchers are developing the new technology using scanning confocal acoustic diagnostic imaging for diagnosis and low-intensity pulsed ultrasound technology for treatment. Compared to current diagnostic ultrasound scanners, Qin's new technology is more advanced because of its ability to assess a higher number of parameters and is designed for imaging of hard tissue such as bone.
"Our new ultrasound technology can detect bone mineral density. In addition, we can assess bone quality, such as stiffness, and then predict the risk of fracture," Qin said. "Overall bone quality assessment, including strength and structure, is essential because the risk of fracture is probably more related to the quality of a bone rather than the density of a bone alone."
On Earth, X-ray machines are the standard tools of choice for monitoring bone health, but they are only used to detect bone mineral density. X-ray machines are not ideal for use in space due to the health risk radiation poses to astronauts, who are exposed to higher levels of radiation outside of Earth's protective atmosphere and magnetic field.
Qin is currently conducting clinical evaluations of the diagnostic part of the technology. The mobile device runs off of a laptop computer, and an image of the heel or wrist can be completed in about five minutes. Also under development is the capability to scan the knee and hip.
Meanwhile, the group is continuing development of the therapeutic portion of the technology. On Earth, it takes six weeks to heal a fracture in normal conditions. The healing process may take longer in space. He said the device will help accelerate fracture healing by stimulating bone regeneration.
Ultrasound has been used to heal fractures, but it has not been effective due to its lack of accuracy at the fracture site. This is where Qin's guided approach will be beneficial. "We are trying to use ultrasound technology as a way to get an image of the fracture site," Qin said. "An integrated probe will directly shoot ultrasound into the region of the fracture. We hope this will result in effective acceleration of fracture healing."
SCAN technology will be an ideal tool for health care providers on Earth who are dealing with an increasing elderly population and for those in rural areas where access to medical facilities is limited. In addition to being small and easier to use than X-ray based bone density measurement machines, the ultrasound device could be as much as 10-times cheaper to purchase and operate. "If we can provide a cost-effective, easy to operate machine at the doctor's office, then they can monitor patients at minimal cost," Qin said. "Also, it is non-invasive and non-destructive. People are not hesitant to get additional tests."
Qin's project is one of nine currently in the NSBRI Smart Medical Systems and Technology Team's portfolio devoted to developing new integrated medical systems to assist in delivering quality health care in space. Other areas being researched include space surgery and supporting techniques, routine risk and health-monitoring systems, and automated systems and devices to aid in decision-making, training and diagnosis. The new systems will have immediate benefits for health care on Earth.
Non-invasive ultrasound therapy targets brain disorders, offers hope