A USC team 3D-printed conductive silver ink onto a thermoplastic elastomer to make patient-specific MRI coils in less than 10 minutes for about $30. In testing, the coils produced roughly four times greater image contrast than standard commercial versions.
MRI coils pick up the radio signals used to form an image, and a closer fit yields a stronger signal. Standard hardware is sized for adults, so it can leave gaps on an infant or child, and a custom coil can cost thousands of dollars and take months or years to make. After about three years of testing flexible materials, plastics, and printable metals, Yasser Khan’s lab at the USC Michelson Center for Convergent Bioscience printed silver ink onto a thermoplastic elastomer that stretches roughly 5% to 10%, so the coil can bend and move with the body. The group also built electronics to connect the unconventional coils to a scanner. Because the parts start as digital files, size and shape can be changed on a computer and a new coil printed.
Khan, an assistant professor of electrical and computer engineering and biomedical engineering at the USC Viterbi School of Engineering, compared the mismatch to using the wrong camera lens. “If you use a large lens to image something very small, you’re not going to get the clearest picture,” Khan said. “But if you can tailor the lens, in this case the MRI coil, to the individual patient, you can capture a much better image.”
The coils were tested with MRI hardware at USC’s Dynamic Imaging Science Center, led by Krishna Nayak, which is used to image anatomy in motion, including a beating heart. John Wood, director of cardiovascular MRI at Children’s Hospital Los Angeles, advised on pediatric heart imaging. The work appears in Nature Communications as Improved dynamic MRI of the wrist and heart at 0.55 T enabled by rapid 3D printed flexible coils
Source: eurekalert.org
