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First Image Taken With an Ultra Low Field MRI
KentuckyFC writes "MRI machines are about to get smaller, much smaller. Most of their bulk is taken up by the huge superconducting magnets required to generate fields of a few Teslas. Now a team at the Los Alamos National Lab in New Mexico has built a machine that can produce images using a field of only a few microTesla (PDF, abstract here). So giant superconducting magnets aren't necessary, a development that has the potential to make MRI machines much smaller, perhaps even suitcase-sized. The one-page paper shows sections of the first 3D brain image taken with the device."
I thought the images were of monkeys at first, however when I went to have a look at MRI images of a human head was thankfully proven wrong (some of us have our monkey origins hidden better than others).
So, for comparison here is a page with images of human heads in a normal MRI.
(single image here)
I hope they get the focusing better (which is what I understand the power is used for) because this will be a good progression.
liqbase
Another company, Vista Clara, is using a novel form of ULF MRI to map groundwater.
Very nice. The images are still very blurry (resolution 81×61×11), and the detectors, at 37mm, are big, but it's a start.
about 50 microteslas http://hypertextbook.com/facts/1999/DanielleCaruso.shtml.
according to the Fine Article:
The measurment field in the article is 46 microteslas.
(A "pre-polarization" field of 30 mT (milliteslas) is appled for one second before each meaurement)
The Larmour frequency for 30 mT is about 1.28 MHz, which is in the AM broadcast band. Interference is likely to be a significant problem.
I was going to make some witty comment about the bullet not going very far, but then again lead isn't paramagnetic, is it? :)
Nope, though not all bullets are lead.
Jokes aside, the field is very strong and ALWAYS on. The oxygen cylinder incident killed the kid who was in the MRI machine at the time; gooooo White Plains Medical center!
Another benefit I forgot to mention is that the machine won't need to be powered up for very long, nor will it need to be quenched in the event of an emergency (which entitles dumping all the electrical energy into heat. Sometimes accidentally, like when the liquid helium coolant drops too low.) It also opens up avenues for people who have metal implants to get MRIs. It's not just magnetic attraction that is a problem; metal can be heated up by the rapidly switching field during an actual scan. High strength MRIs already do this in your *body* because of its conductivity!(we're talking the newest, highest strength human-clinical machines. Research MRIs well exceed clinical machines, and a lot of clinical machines are only a few tesla.)
Please help metamoderate.
Its not like the effect used in NMR is _only_ viable at high field strengts.
Its just that higher fields (or more correctly put, higher field gradients) allow for higher resolution.
Looking at this publication, they archived about 5mm resulution with a 50uT field.
Real high-end small bore scanners can get 3 orders of magniture higher.
And the "maybe can it fit in a glovebox" part is _severely_ limited by the use of 7(!) Squids... Each of which will need a LN/LH cryosystem.
Still, this looks quite interesting, but its not like it completely depricates the current stuff.
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
I had to have several MRI & CT scans and that friggin tunnel is more than I can handle.
I haven't seen one in person yet, but there's apparently a company which produces something called the Fonar 360, which instead of having a tunnel basically turns the entire room is a magnet. This is useful not just for reducing claustrophobia, but also hypothetically allows for surgery to occur while somebody is inside of an MRI. I think the spatial resolution however is quite a bit weaker than typical scanners.
The same company also has an Upright MRI product, where the patient sits down with open space in front of them.
For cancer scanning, you'd really want a PET (positron emission tomography)
Ian Ameline
No. It can say "the machine was unable to detect any of the types of large solid tumors we can recognize".
.. cause those products still exist on the market.
Do people sue pregnancy test kits if it tells them they weren't pregnant and they drank alcohol and the baby was born with problems? Or condom manufacturs for getting deadly diseases?
If they do, they havent been very successful
Disclaimers. Use them.
DISCLAIMER: The above post is not meant to encourage or discourage anyone from getting into the home MRI business. Author assumes no liability for failure of any home MRI ventures or investments. Your success may vary. Results not typical.
I believe the post you are referring to mentioned a CT scan, not an MRI. While both are imaging techniques, they are quite different in how they work. MRIs are much, much more expensive in general. They require the supercooled magnets and such. A CT is essentially using the same type of radiation as in used in a normal X-RAY to get sliced images. CTs are much faster at acquiring images and the equipment is much cheaper than an MRI. Both of the factors make it much less expensive overall.