A portable Magnetic Resonance Imaging (MRI) device from the Los Alamos National Laboratory uses low-power magnetic fields to image the brain and other soft-tissue anatomy. The lightweight technology could be deployed on the battlefield and in the world's poorest regions.
Hospital-based MRI devices are big and require considerable infrastructure, such as large quantities of liquid nitrogen and helium. Large magnetic fields align the protons in water molecules to then create magnetic resonance signals, which are detected by the machine and turned into images.
Michelle Espy, the Battlefield MRI (bMRI) project leader, and her team used Superconducting Quantum Interference Devices, or SQUIDs, to achieve images at ultra-low magnetic fields.
"SQUIDs are so sensitive they'll respond to a truck driving by outside or a radio signal 50 miles away," said Al Urbaitis, a bMRI engineer.
The team's first generation bMRI had to be built in a large metal housing in order to shield it from interference. The Los Alamos team now works in the open environment, using a lightweight series of wire coils that surround the bMRI system and compensate the Earth’s magnetic field.
