In this short article, Popular Science reports that a Brown University team has developed a new imaging system. The CTX process combines 'computed-tomography (CT) scanners, X-ray video and computer software to give doctors and researchers a 3-D look at bones in motion.' In a previous note, the team said that 'CTX technology is expected to deliver images with exceptional precision and detail. Researchers will be able to track 3-D skeletal movements with 0.1 millimeter accuracy and see the equivalent of 1,000 CT images per second.' A commercial system should be ready by 2010.
Here is an example of what can be achieved with the CTX technology. You can see above two series of images of a pigeon in flight. "For this sequence, researchers manually aligned, frame by frame, a 3-D digital skeletal model from CT scanning with a digital X-ray video sequence to create a complete 3-D reconstruction of skeletal movements." As you can see, digital X-ray (top) provides less details than the CTX method (bottom). (Credit for images: Stephen Gatesy, Brown University) Here is a link to other images and movies using the imaging CTX system.
This research work has been supervised by Elizabeth Brainerd, a professor of ecology and evolutionary biology, and the members of her Functional Morphology & Biomechanics Laboratory including Stephen Gatesy mentioned above.
But what is exactly CTX technology? Here is the short answer from Popular Science. "The new process, known as CTX imaging, combines both of these technologies to produce 3-D animations of bones in motion -- walking, running, jumping. Though still in prototype form, the room-size system is already helping researchers to answer tough questions about animal biomechanics, such as how flight evolved in birds. It could also be a valuable tool for orthopedic surgeons, who might use it to plan better treatments for bone-, ligament- and joint-related injuries.
The February 2007 Brown University news release provides additional details. "This will be like having X-ray vision -- you’ll be able to see through skin and muscle and watch a skeleton move in 3-D," said Elizabeth Brainerd, the Brown University biology professor overseeing development of the new system. "Imagine animated X-ray movies of flying bats or flexing knees. It's very cool technology that is also very important from a biomedical standpoint."
Obviously, several medical-imaging technologies already exist, but this one will fill a void in medical and scientific imaging. Right now, researchers trying to understand the complex motions of bones and joints are held back by technology. Computed tomography, or CT, delivers detailed 3-D images, but CT scanners are too slow to capture rapid motion. Cinefluoroscopy, a technique that uses X-rays to view objects, can produce moving images in two dimensions, but not 3-D."
The CTX system could be used for a number of applications, such as testing new theories of biomechanics, planning orthopedic surgeries, or creating better treatments for shoulder, wrist, knee and back injuries. But the software behind the technology is not ready yet, so you'll have to wait until 2010 to watch a skeleton in 3-D in real time.
Sources: Eric Mika, Popular Science, June 2007; Brown University news release, February 1, 2007; and various websites
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