The world’s most powerful magnet for full-body imaging scans has arrived at the University of Minnesota, where it is expected to attract millions of dollars in research grants and play a significant role in a national project to map the human brain.
The 110-ton magnet was made by Agilent Technologies in England, then shipped across the Atlantic Ocean and through the Great Lakes to Duluth. It arrived Friday on a 150-foot trailer that was 16½ feet wide and had 64 wheels, operated by Perkins Specialized Transportation of Northfield. A team of installers took two days to winch the massive, tubular magnet through an open wall of the U’s Center for Magnetic Resonance Research, where it will be encased in a custom-built iron box to keep it from disabling nearby electronics and harming researchers.
Once energized, the new MRI will produce 10.5 Teslas, a unit of measure that describes the strength of a magnetic field. By comparison, most hospitals use MRI machines that produce 1.5 or 3 Teslas. The stronger the magnet, the finer the image it produces.
“The kind of information that we need to generate an accurate wiring diagram of the human brain simply doesn’t exist,” said Kamil Ugurbil, director of the U’s MRI research efforts. “This will enable us to be unique in terms of human brain studies.”
Ugurbil is one of two principal investigators in the Human Connectome Project, which seeks to map the brain.
He is also part of a national working group helping to steer a $100 million project backed by President Obama.
Called the NIH BRAIN Initiative, it aims to do in 10 years for brain research what the Human Genome Project did for genetics.
The new MRI, he said, will put the U in good position to receive grants related to the initiative because it will produce significantly better information about the brain’s structure and functioning.
Brain research is kicking into high gear in advance of what’s been called the “silver tsunami” of age-related disorders like Alzheimer’s disease and other dementias, which threaten to swamp the health care system as the population ages. The research also may lead to advances in battling neurological disorders such as autism, epilepsy, Parkinson’s disease and amyotrophic lateral sclerosis, commonly called Lou Gehrig’s Disease.
720 miles of wiring
The U pioneered the use of high-energy magnetic fields to study brain function about 20 years ago with a 4-Tesla machine. Subsequently, it designed and built the first 7-Tesla MRI, which is currently the most powerful approved for use in human studies. A 7-Tesla machine can resolve down to about a cubic millimeter, or about 80,000 neurons, The 10.5-Tesla machine should enable researchers to penetrate down to a couple of tenths of a cubic millimeter.
If all goes well, it will take until July to hook up the unit’s sophisticated electronic instruments and cool down the magnet’s 720 miles of superconducting wiring with liquid helium to 2.5 degrees Kelvin.
The 10.5-Tesla MRI was conceived in 2008 and funded by an $8 million grant from the National Institutes of Health. It would be operating already but for a worldwide shortage of liquid helium. The MRI requires 40,000 liters of the coolant.
Work initially will begin on animals to prove that the technology is safe. Ugurbil said studies with a 9.4-Tesla machine already have proved safe in animals.
The new MRI, like the existing 7-Tesla models, will have an internal bore of about 60 centimeters, or just under 2 feet, once the final electronics and shielding materials are added. That should accommodate most of the population, a factor he said was critical in its design. Each centimeter increase in the machine’s size adds millions of dollars to the price.