University of Minnesota to house world's largest magnetby Tom Weber, Minnesota Public Radio
Minneapolis — A ceremony Thursday at the University of Minnesota marked the start of construction of a building that will one day house the world's most powerful magnet.
That magnet and others help researchers diagnose and treat any number of diseases, from cancer to Alzheimer's to schizophrenia.
Using magnets in medicine isn't new. Using magnets this big on humans will be.
"I'm excited about the research we'll be able to do," said Michael Garwood, associate director of the U's Center for Magnetic Resonance, which houses the machines right across the street from the new football stadium. "The things we'll be able to measure that you haven't been able to measure before."
The very oversimplified version of this science is there are very small, very weak magnets inside the molecules that make up our body parts. A strong-enough magnet outside will interact with those very weak magnets inside and the energy from that interaction will create a signal that can be tracked and made into an image.
That's what MRIs do, mapping not just what our brains look like, but also what they're doing. And the bigger the magnet, the more you can see.
Magnets' power are measured in Tesla, and the ones in those MRI clinics that maybe you or a family member has been in are between 1.5 and 3 Tesla. The U already has a 4 Tesla machine, a 7 Tesla machine, and a 9.4 Tesla machine.
Today's groundbreaking marked the start of construction on a $53 million building that will house a 10.5 Tesla machine. The magnets themselves are $14 million of that cost.
The main aim of a bigger, stronger magnet is discovery. Nine Tesla can't detect some chemicals, and some chemicals are tell-tale signs that you have this illness. So, the hope is that a 10.5 Tesla will pick up a bunch of new stuff and help researchers tell a patient "we found this, so you might have that."
Center director Kamil Ugurbil also said housing the world's largest magnet could draw more research dollars to Minnesota.
"Neurosurgery, to psychiatry, to psychology to orthopedic surgery -- essentially there isn't a discipline in medicine we don't touch," Ugurbil said.
Michael Garwood went to see the existing, smaller magnets this morning, but not before a stop at a locker. Before entering, visitors and researchers must remove their wallets, credit cards cell phones and watches to prevent them from being killed by the powerful magnets.
But here's a dumb question - if the magnet is so powerful, how come cars driving by won't be drawn in? The answer is distance.
Remember in science class - those drawings of the loops that magnetic fields make? As long as you're outside the loop you're outside the magnetic field.
The rooms are encased in steel, which knocks down the magnetism a little -- but more importantly, it keeps stuff out, like radio and TV signals that would mess with the magnets. The rooms, though, look like any MRI clinic. The patient lies on a table that's slid into the donut-shaped machine, so the magnets can be all around, gathering images. The only difference is the big, huge new magnet will be twice as large as a normal MRI machine.
Garwood assured that it's safe, adding that's why researchers like magnets so much. There's no harm, like you might have with radioactivity.
"People have worked around these magnets for decades, and there's been nothing that's appeared to be anything to be concerned about," Garwood said.
The building is slated to open in fall of 2010. The magnet will weigh 60 tons and be built in England. They'll then ship it to Duluth, then drive it down I-35 on a specially made truck. Drivers need not worry about driving next to the truck, though. Unlike refrigerator magnets, which are always on, so to say -- these machines only produce magnetic fields after you've added liquid helium.
- All Things Considered, 08/20/2009, 5:25 p.m.