New ‘glove’ can capture images of the body in motion
A new magnetic resonance imaging technology attached to clothing can provide high-quality images of bones, tendons and ligaments as they move, opening the door to advances in the understanding and care of soft tissue.
The study, led by the NYU School of Medicine, specifically looked at capturing images of the hand by creating a specially designed prototype MRI “glove,” according to a new study in Nature Biomedical Engineering.
Current MRI technology only takes still images. MRI works by putting tissue in a magnetic field, which creates magnetic force. The key to extracting information is by deliberately disturbing the hydrogen atoms in the tissue by using radio waves to make them spin and emit radio signals, which reveals their positions—this information is then rebuilt into images. MRI scanners measure the signals, which create electrical currents in radiofrequency receiver coils/detectors.
However, the electrical currents also impact nearby coils/detectors, preventing them from obtaining clean signals. The way to resolve this problem has been to cancel out magnetic fields in nearby coils by not allowing them to move when images are being taken.
This rigidity makes the images less useful. It also limits the ability to capture images of tendons and ligaments, because they’re made of dense proteins, not liquid. MRI it works best at imaging soft tissues made of water, such as muscles, nerves and cartilage.
The researchers theorized that if they created receiver coils that made it harder for the electrical current to flow, they may be able to avoid having to keep the coils rigid because they would no longer create magnetic fields that interfere with each other.
They designed new “high impedance” coils with the help of a 3-D printer and computer-aided design and stitched eight of them into a cotton glove.
Researchers then conducted a series of imaging experiments with volunteers wearing the glove.
They found that the new coils enabled the MRI to visualize in “exquisite detail” the dynamics among the ligaments, tendons and muscles during complex motions, such as playing the piano or grasping a peach.
“[This new design] open[s] up new avenues for the study of complex joint motion, promising to facilitate, for example, the diagnosis, monitoring and treatment of repetitive strain injuries in athletes, musicians and others,” The study authors state. It can also advance the knowledge of anatomy, guide surgery with images in more realistic positions, and help design better prosthetics.
The researchers hope that their study “ushers in a new era of MRI design” including MRI sleeves to diagnose knee injuries and a beanie to study brain development in newborns, says senior author Martijn Cloos, assistant professor at the Center for Advanced Imaging Innovation and Research within the Department of Radiology at NYU Langone Health.
Their next step is to take the study to the next level.
“We plan to build another glove coil, made out of better quality materials to maintain a close fit on the subject’s hand (our original 5-dollar cotton glove is falling apart now). This glove will also have more coil elements made out of even more flexible material. The goal is to make this second coil robust enough for frequent use. This could be a stepping stone towards more rigorous volunteer/clinical evaluation,” Cloos says.