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First Image Taken With an Ultra Low Field MRI
Posted by
kdawson
on Sat Nov 10, 2007 01:57 PM
from the swimming-with-the-squids dept.
from the swimming-with-the-squids dept.
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."
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Hidden monkeys (Score:4, Informative)
So, for comparison here is a page with images of human heads in a normal MRI [fbi.gov].
(single image here [fbi.gov])
I hope they get the focusing better (which is what I understand the power is used for) because this will be a good progression.
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Article's title is misleading (Score:4, Informative)
Another company, Vista Clara, is using a novel form of ULF MRI to map groundwater.
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Bert
Re:Article's title is misleading (Score:5, Informative)
This isn't an ultra low field MRI, it's a DUAL field MRI. In a normal scanner you have a big, static magnetic field that polarizes the sample and remains for readout. In one of these dual field scanners you use the big field (or a bigger field, it's usually a resistive electromagnet so it can't be anywhere near as strong as a superconductor) to polarize the sample then you shut it off and use a much smaller field for readout. There are a few advantages, the one the abstract focuses on is that you can do things like MEG in a very low field. The other is that energy deposition is related to the field strength so by using a small field you can use imaging sequences that would otherwise pump too much energy into the subject.
One of the guys working on this technology visited my lab last year. It was a very interesting presentation.
I believe someone has produced an MR image using the Earth's magnetic field. They've certainly done nMR in the Earth's field. You can't get much lower than that on this planet.
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Re:Article's title is misleading (Score:4, Informative)
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Stronger pre-polarizatin field is used (Score:4, Interesting)
Re:Stronger pre-polarizatin field is used (Score:4, Informative)
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If that was the reason, they would just pre-polarize to a different field. Most MRI happens in the middle of some radio band, and at ~2 KHz, there is going to be lots of interference from 60/50 Hz harmonics or other mains related EM radiation. The interference is removed by shielding the magnet / room. In this case, I think they also used a gradiometer coil which is pretty
MRI accidents (Score:4, Interesting)
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Not that they're common, but still, those things aren't toys.
Thank you for pointing out that MRI's are not toys.
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She said "I don't want to leave my purse behind. I'll hold it really tight."
The tech said "You can't hold it. It'll tear your arms off."
She said "I'll just set it on a chair next to me."
He said "You can't bring it with you. There's a big magnet in the room and it
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other implications (Score:4, Interesting)
Plusses: less (very expensive) liquid helium or (less expensive but still $$) liquid nitrogen. Less of a magnetic field means much higher MRI safety; everything from oxygen cylinders to chairs to guns have been drawn into/against MRIs (the gun was a prison guard who got pushy and DEMANDED to be in the same room as a prisoner. Yeah, the gun went off. No, nobody was hurt.)
Negatives: since the MRI isn't as strong, it might be more affected by local magnetic fields from wiring, ferrous objects, etc. Dunno. Right now, MRIs are installed into big rooms that have as little ferrous material as possible, and then very carefully "shimmed" to adjust for the building and local magnetic fields by a technician. Even if an MRI gets down to "suitcase" size, the necessity of a "clean" environment and calibration for each location might make moving them around very tough.
As a side note, there are already shielded MRI machines which work in a trailer and require little setup time, but being outdoors makes things easier- no building infrastructure to mess with the magnetic fields.
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I was going to make some witty comment about the bullet not going very far, but then again lead isn't paramagnetic, is it?
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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
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Re:other implications (Score:5, Funny)
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Another similar story, an MRI facility in Arkansas had just been built and the Fire Marshal was on his way to do the final inspection. However, before he got there, the sprinkler contractor decided to take the oxyacetylene torch rig into the room to fix a leaky sprinkler head. The magnet grabbed the tanks, drew them inside, snapped the valve off
Getting there, but not there yet. Too low-rez (Score:3, Informative)
Very nice. The images are still very blurry (resolution 81×61×11), and the detectors, at 37mm, are big, but it's a start.
I hope they do away with the tunnels (Score:4, Interesting)
They tried to put me in one with the normal little tunnel (about as big around as a five gallon bucket) and I freaked out before I got 2' into it and made them back me out. Then they put me in an "open" MRI machine but it was like being crushed under a car. No way Jose. Abort #2.
So I went to another city where they had a different kind that was a little more "open" than #2.
This one then pumped me full of Xanax and I survived it.
The CT scan was not quite as bad because it was like a large doughnut and there was only about 1' of my body inside it but it still freaked me out.
Xanax on that one too.
I swore I'll die before I ever go in one of those damn things ever again.
They need to come up with a better way. Some people can't handle that crap.
I hope these new ones are a break away from the "trapped in a pipe" or "crushed under a car" machines.
Re:I hope they do away with the tunnels (Score:4, Insightful)
Of course I understand completely that people don't have to justify their phobias, but you have to admit that you must have caused quite a few shaken heads, raised eyebrows, and sighs of exasperation on behalf of the medical staff. Especially considering that because of their scarcity such machines usually have a line of people waiting for them.
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Re:I hope they do away with the tunnels (Score:5, Insightful)
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Re:I hope they do away with the tunnels (Score:5, Insightful)
I realize that many people find it difficult to understand the lack of control inherent in a phobia. I (with my injection phobia) am often told (by medical professionals) simply to get over it. Unfortunately, when a needle is present, I descend into blind animal panic. My rational mind ceases to function. The thoughts of controlling and pushing through the fear don't even occur to me. It is a pure flight-or-fight response, and I have done both.
Additionally, the guilt of having wasted time (of the doctors or other patients) needlessly adds to the unpleasantness of the situation. His attempts to undergo the procedure are, in my opinion, courageous.
People need help, not guilt or reprimands.
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As far as the claustrophobia goes, MRI is a bad time to find out.
Re:I hope they do away with the tunnels (Score:4, Insightful)
Why not use a cloth eye cover?
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All kidding aside, I've had two MRIs in the last few years. I'm not at all claustrophobic, so the tube doesn't bother me; I've been in tighter places than that several hundred feet underground. Just close your eyes, listen to the nice music, and try not to think about it.
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I haven't seen one in person yet, but there's apparently a company which produces something called the Fonar 360 [fonar.com], 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 s
for reference, Earth's magnetic field is (Score:2, Informative)
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)
Smaller == Cheaper (Score:2, Insightful)
In home MRI scanner (Score:4, Interesting)
Basically the device would be conveniently rolled over the bed once a month or so and scan. It will utilize advanced 3D image analysis to compare with last couple month's scan and see if you have any growing tumors. If so then you go get a proper scan done.
This will go well with the "in toilet" piss or shit tester that will tell you if you're going diabetic or may be developing some other medical conditions for example like kidney disease or cancer, etc..
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because it will interfear with our tin foil hats of course.
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For ultrasound systems, a far cheaper technology, the cheapest systems seem to be around $10,000. And while I could see the geek appeal of messing around with ultrasounding various animate and inanimate objects, I am sure that if the price should reach sub-1000's, it would quickly become another weapon in the arsenal of hypochondriacs and hysteric pregnant wome
No (Score:3, Informative)
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 b
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Lower health care costs? (Score:2)
Technology certainly doesn't have all the answers, but things like this can only lead to good.
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While some of your hospital bill is due to the cost of acquiring and maintaining the expensive machines, are you also aware that part of your bill is due to people who use the hospital's services but
Nothing _that_ new... (Score:3, Informative)
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.
Re:Nothing _that_ new... (Score:4, Informative)
If you've got lots of time you can achieve more or less any resolution you want with any field strength you like. The problem is, the darn patients keep getting impatient and moving.
The summary is pretty wildly inaccurate. This is actually a dual field scanner that uses a stronger field to polarize the sample and a weaker one for readout. It's pretty cool, but it's a niche thing... these guys want to do MEG scanning along with MRI and MEG is allergic to large magnetic fields. It won't be replacing the regular superconducting scanners and it won't be making cheap in-home scanners possible.
You can do nMR in the Earth's magnetic field if you want to. It's actually possible to set it up at home. I think someone was selling science kits for a while.
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Re:Oy! My payments... (Score:4, Insightful)
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Re:Oy! My payments... (Score:5, Insightful)
You know, just a thought.
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When you can figure out how to do that without holding a gun to my head to force me to pay for it, I'll back you 100%.
maybe a little bitter about this (Score:5, Insightful)
It's a good thing I did get that expensive modern medical advance in America, though, because of the high-quality analysis and follow-up I got from the clinic. In total, I got one sentence out of it- "Your intestines are a little constricted." I don't think they could provide that kind of advanced analysis in India with their cheap CT scans.
I guess I'm wondering- are modern medical advances really as expensive as we're led to believe they are in America?
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Medical research happens when there's money behind the disease. Once the advance is made and commoditized for great loads of money to the first world (and the research is the main thing priced, not the build construction), it can be exported to the developing world and add value slightly to their firstworld sales numbers, for little extra effort.
If the first world didn't exist, then the developing world wouldn't have the luxury of down-marketting - they would have to get by without the tech bein
Re:Oy! My payments... (Score:4, Interesting)
About the article: those pictures are pretty unclear but it's promising.
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Re:We have determined that your brain configuratio (Score:3, Funny)
We have determined that your brain configuration predisposes you to rebellion
(read that as: your head is still attached to your shoulders)