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Biotech Science

First Image Taken With an Ultra Low Field MRI 189

Posted by kdawson 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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First Image Taken With an Ultra Low Field MRI More

First Image Taken With an Ultra Low Field MRI

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  • Hidden monkeys (Score:4, Informative)

    by LiquidCoooled ( 634315 ) on Saturday November 10, 2007 @02:59PM (#21308117) Homepage Journal
    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 [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.

  • Article's title is misleading (Score:4, Informative)

    by IvyKing ( 732111 ) on Saturday November 10, 2007 @03:07PM (#21308169)
    This may be the first image of a human head with an ultra low field MRI, but ULF MRI images have been made for at least a decade and a half. Magritek, a New Zealand company, makes a low cost unit ULF MRI system, though the image volume is limited to about one liter.


    Another company, Vista Clara, is using a novel form of ULF MRI to map groundwater.

    • Re: (Score:2, Funny)

      by kanweg ( 771128 )
      Should be big enough for early creationists.

      Bert

    • Re:Article's title is misleading (Score:5, Informative)

      by ceoyoyo ( 59147 ) on Saturday November 10, 2007 @05:14PM (#21308913)
      The summary is VERY incorrect.

      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.

  • Stronger pre-polarizatin field is used (Score:4, Interesting)

    by flyingfsck ( 986395 ) on Saturday November 10, 2007 @03:07PM (#21308177)
    Hmm, they use a prepolarization field of 30 mT for 1 second before using the weaker measurement field of 46 uT. So I'm wondering why they don't just use the 30 mT field and be done with it.

    • Re:Stronger pre-polarizatin field is used (Score:4, Informative)

      by IvyKing ( 732111 ) on Saturday November 10, 2007 @03:28PM (#21308323)
      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.

      • Re: (Score:2, Interesting)

        by Anonymous Coward

        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.

        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

        • Re: (Score:2)

          by IvyKing ( 732111 )
          It's easier to make a gradiometer work well at low frequencies where the electric field pick-up can be ignored. The interference from the 50/60 Hz power lines is fairly stable and it is possible to get pretty significant attenuation of that interference source.

          The one advantage of using the earth's field is that it is reasonably uniform in a clean environment, and the pre-polarizing field doesn't need to be anywhere near as uniform as the readout field. In a not so clean environment, it is possible to us

    • Re: (Score:2)

      by ceoyoyo ( 59147 )
      They want to do MEG and MRI together. MEG measures small magnetic fields in the brain. MEG doesn't like big magnetic fields. The stronger your polarization field is though, the better signal to noise you get.

    • Re: (Score:2)

      by awfar ( 211405 )
      I suggest that the point is to demonstrate minimal power, and that 30mT is necessary to disrupt and homogenize any local static and pre-magnetization of the sample. This seems like it would be necessary since any ultra low field perturbation and later measurement would be overwhelmed.

  • MRI accidents (Score:4, Interesting)

    by l00sr ( 266426 ) on Saturday November 10, 2007 @03:09PM (#21308185)
    Hopefully this will also put an end to those pesky MRI accidents [nytimes.com]. Not that they're common, but still, those things aren't toys.

    • Not that they're common, but still, those things aren't toys.

      Thank you for pointing out that MRI's are not toys.

      ;-)

      • Clearly you're ignoring the Fisher-Price MRI for Tots toy, priced at a reasonable $500,000 for discerning parents who want their kids to go to Harvard someday. And besides, it's always fun for a kid to force his little sister to put her head in a superconducting magnet chamber or face evisceration of her dolly.
    • Makes me wonder if they'll be able to throw you in an MRI without removing your metallic objects. Or even a Terminator-style MRI-based walk-through security scanner?

      • Re: (Score:3, Interesting)

        by tsa ( 15680 )
        That's what I thought. People with a pacemaker for instance, can not be imaged with an MRI anymore now. Hopefully that'll change in the near future.

      • Re: (Score:2)

        by SnowZero ( 92219 )

        Makes me wonder if they'll be able to throw you in an MRI without removing your metallic objects. Or even a Terminator-style MRI-based walk-through security scanner?

        That scanner [scifi.com] was from Total Recall [imdb.com]. For better or worse, we're not that far off [geardiary.com].

    • Re: (Score:3, Funny)

      by myth_of_sisyphus ( 818378 )
      I was in a gown prepared to get an MRI for my back and a little old lady in the waiting room with me refused to give the MRI tech her purse. She was in a gown holding her giant purse with metal snaps and buckles tightly. (An amusing image. I lol'd)

      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

  • other implications (Score:4, Interesting)

    by SuperBanana ( 662181 ) on Saturday November 10, 2007 @03:10PM (#21308189)
    Off the top of my head, some plusses and negatives.

    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.

    • Re: (Score:2)

      by Dunbal ( 464142 )
      Yeah, the gun went off. No, nobody was hurt.

            I was going to make some witty comment about the bullet not going very far, but then again lead isn't paramagnetic, is it? :)

      • Re: (Score:3, Informative)

        by SuperBanana ( 662181 )

        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

    • Re: (Score:3, Interesting)

      by ScrewMaster ( 602015 )
      Some twenty-odd years ago when I was doing some research software for a teaching hospital in the city, I had noticed there was some significant construction going on, some kind of addition to the main building. I didn't know what it was for at the time. A couple months later I was walking down a hallway with one of the doctors I was working with, and noticed what looked like a two-foot-square hole in the wall that hadn't been there the day before. It had been crudely patched with plasterboard. The doctor to

      • Re:other implications (Score:5, Funny)

        by 2short ( 466733 ) on Saturday November 10, 2007 @07:16PM (#21309587)
        Ten years ago my girlfriend at the time was involved in research using NIHs 4T human machine, a 3-story tall superconducting magnet. There was a fence outside part of the building with signs saying keep out, strong magnetic fields. But one day my girlfriend told me how the director had to go running outside because some workmen digging a trench were taking down a section of the fence, preparing to bring a backhoe through. After arguing a bit with the construction foreman about this being where the trench was supposed to go, and how he really didn't think a magnet was going to hurt his backhoe, she took one of their shovels and stuck it to the wall. That got their attention long enough to explain how many millions of dollars they would owe her if their backhoe gets sucked though the side of the building and breaks her magnet.

        • Re: (Score:3, Interesting)

          by tgilk ( 1187517 )
          Man, I'd love to get the details on that! I'm an architect that specializes in MRI facility design & construction and I'd love to be able to document that story.

          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

      • Re: (Score:2)

        by ceoyoyo ( 59147 )
        Either someone was putting you on or that centre was criminally badly designed. You also don't really "test fire" a high field MR magnet. You ramp it up slowly to full power and then it stays there indefinitely.

        The fringe field for even a large high field magnet doesn't really extend all that far. The 5 Gauss line (go across that and you might get your credit cards erased but it STILL won't make anything fly) is maybe 15 feet from the magnet. It's just far enough that the line goes through the middle of
        • s/indefinitely/until quench/

          And the quench is not always planned...

          • Re: (Score:2)

            by ceoyoyo ( 59147 )
            Indefinitely: not definite; without fixed or specified limit.

            In other words the magnet remains stable for a non-predetermined amount of time, which you hope is a long time.

      • The doctor told me that a workman had been walking by carrying a window air conditioner at the exact moment the operator was test firing the magnets for the new MRI center they had just built right next door.

        That's a cute story, but also shows a complete lack of knowledge of how MRIs work. The magnet is always on. The noise you hear during an MRI is the field switching, physically loading the coil. Anyway, you don't 'fire up' an MRI magnet, you "ramp" it up; they have to be charged slowly, using a spe

    • Re: (Score:2)

      by torkus ( 1133985 )
      FYI, liquid N2 isn't really that expensive. On the order of $20 per litre in small quantities.

      Buy a couple hundered gallons and it'll be much cheaper. In fact, you start getting to the point where it's cheaper to make it youself. Since most hospitals make and store LOX, it shouldn't be too difficult.

      • Buy a couple hundered gallons and it'll be much cheaper. In fact, you start getting to the point where it's cheaper to make it youself. Since most hospitals make and store LOX, it shouldn't be too difficult.

        If you had the slightest idea what you were talking about, you'd know that liquid oxygen has a higher temperature than liquid nitrogen. This is actually a danger of working with LN; you can end up with oxygen condensing in something you're cooling in LN.

        They also consume quite a bit of LOX, so it's

  • Getting there, but not there yet. Too low-rez (Score:3, Informative)

    by Animats ( 122034 ) on Saturday November 10, 2007 @03:10PM (#21308193) Homepage

    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)

    by pair-a-noyd ( 594371 ) on Saturday November 10, 2007 @03:11PM (#21308201)
    I had to have several MRI & CT scans and that friggin tunnel is more than I can handle.
    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)

      by Dunbal ( 464142 ) on Saturday November 10, 2007 @03:21PM (#21308275)
      For some reason I find that your comment suits your screen name just fine...

      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.

      • Re:I hope they do away with the tunnels (Score:5, Insightful)

        by kailoran ( 887304 ) on Saturday November 10, 2007 @03:45PM (#21308427)
        I'd assume those shaking heads were muttering "geez, another one" rather than "omg wtf how can someone be afraid of it". Claustrophobia isn't all that unheard of, and being shoved into a friggin pipe is somewhat a powerful trigger.

        • Re: (Score:3, Insightful)

          by tsa ( 15680 )
          It's indeed scary to be in that pipe. Not only is it very narrow and you can't get out yourself, but the machine makes very loud noises when in operation. Being inside a working MRI machine is not a fun experience.

      • Re:I hope they do away with the tunnels (Score:5, Insightful)

        by Nyago ( 784496 ) on Saturday November 10, 2007 @03:52PM (#21308479) Homepage
        If it were easy (or even moderately hard) to control a phobia, I suspect most people would. Justification is irrelevant. It matters only that the fear exists. Conquering a phobia typically requires exposure (with neutral or rewarding consequences) to the fear-provoking stimulus. In his case, gradual exposure to being in the tube.

        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.
        • I have acrophobia (fear of heights), so I understand completely. When I'm in a phobia-triggering situation, the effect not merely mental. I feel weak and dizzy, with and odd buzzing sensation going down my spine and other parts of my body.

    • Re:I hope they do away with the tunnels (Score:4, Insightful)

      by RallyNick ( 577728 ) on Saturday November 10, 2007 @03:43PM (#21308409)

      I had to have several MRI & CT scans and that friggin tunnel is more than I can handle.

      Why not use a cloth eye cover?

      • Why not use a cloth eye cover?

        I imagine that wouldn't work - the person with the eye cover on would know that the MRI machine was still out there... waiting to constrict them like an enormous metallic python.
        I had an MRI a few years ago. Having to lie unmoving for so long was a bit surreal, and I got into a kind of self-hypnotized state which made the time seem to go faster. I'm not claustrophobic, but one thing that sort of creeped me out was the tiny mirror that was right in front of my eyes. The effect r
      • We have magnet-compatible goggles with LCD screens in them, because we use the MRI for cognitive psychology experiments where you often want to present visual stimuli. Having these goggles on with something to look at, even if its just a screen saver, really helps a lot.
    • Comment removed based on user account deletion

    • Re: (Score:3, Informative)

      by FleaPlus ( 6935 )
      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 [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
    • 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.

      I agree with you 100%, pair-a-noyd. I'm almost 6' tall and pretty broad across the shoulders. I went to a local hospital for an MRI of my head. I went into the "bore" of the machine headfirst and I had to scrunch up my shoulders so I would fit into the machine. I made it about thirty seconds before I made them pull me out (I had no

  • for reference, Earth's magnetic field is (Score:2, Informative)

    by Anonymous Coward
    about 50 microteslas http://hypertextbook.com/facts/1999/DanielleCaruso.shtml [hypertextbook.com].

    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 is nice, but what really needs to be done is to make them cheaper to purchase and operate. That way, even the local small hospitals can, hopefully, afford one. When you're sick and living out in the country, having to drive a hundred miles to the nearest machine can be quite a chore.

  • In home MRI scanner (Score:4, Interesting)

    by backslashdot ( 95548 ) on Saturday November 10, 2007 @03:22PM (#21308283)
    I wonder if this could finally lead to an "in home" MRI scanner? If it costs under a thousand bucks and a person has a family history of cancer, why not invest in one?

    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..
    • I wonder if this could finally lead to an "in home" MRI scanner? If it costs under a thousand bucks and a person has a family history of cancer, why not invest in one?

      because it will interfear with our tin foil hats of course.

    • Re: (Score:3, Insightful)

      by GrievousMistake ( 880829 )
      Like other medical imaging technologies such as ultrasound, the images are medically pretty much worthless without a qualified operator to read them.
      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
      • The machine is also worthless without a trained operator to use them. It requires knowledge of the body, vascular system, organs, etc to know even where you're looking. The computer doesn't just spit out an answer with the disease, and the operator isn't the one who reads the images. An MD does.
        • Just how do you know the specifications of a machine that does not exist? Please cite a law of physics or chemistry that excludes the machine from being able to analyze images and flag any sort of tumor. Furthermore it can be clearly stated that the machine is no substitute for real checkup. Why should some people have to waste their money on monthly doctor's visit's because a few people may abuse it?

          I bet when MRI machines and X rays were coming out with their low quality/resolution pics you would have bee
      • You realize there are workarounds and solutions for all the things you said?

        For one thing, you're already assuming that it is impossible for the machine to be able to tell the difference between tissue types and also to write good enough image analysis software to tell the difference between real tumors and false positives.

        If the software and hardware is good, the device would reduce the number of visits to the doctor.

        As for hypochondriacs, if false positives can be eliminated it would actually work against

      • Re: (Score:2)

        by ceoyoyo ( 59147 )
        You can build yourself an ultrasound device if you want to, probably for under $50. Most EEG units cost around $50,000 too, but you can build yourself one for $20.

        The extra cost for the real thing is for quality, reliability and insurance.

    • Re: (Score:3, Informative)

      by ameline ( 771895 )
      For cancer scanning, you'd really want a PET (positron emission tomography)

      • For cancer scanning, you'd really want a PET (positron emission tomography)

        That's a good idea. A home scanning technique that requires intravenously-administered, short-half-life-made-on-site-in-a-cyclotron radioisotopes. Er, what?

        PET is something that you would use to confirm a diagnosis (look for metabolic hotspots if cancer is suspected) or detect metastases (tumours distant from the original site). It's never the first tool that a diagnostician reaches for.

        Besides, the resolution of PET is crap

      • Re: (Score:2)

        by ceoyoyo ( 59147 )
        I can imagine what the government would have to say about the home cyclotron you need to go along with that. Of course, if you were in the habit of regularly injecting yourself with a positron emitter you wouldn't really be a problem for long.
  • Maybe this will help bring down health care costs as hopefully these will be a lot cheaper - and hopefully no longer will hospitals in the middle of nowhere have to spend several million dollars on an MRI machine.

    Technology certainly doesn't have all the answers, but things like this can only lead to good.
    • Maybe this will help bring down health care costs as hopefully these will be a lot cheaper - and hopefully no longer will hospitals in the middle of nowhere have to spend several million dollars on an MRI machine. Technology certainly doesn't have all the answers, but things like this can only lead to good.

      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
      • In a restaurant, the choice is "eat here or eat somewhere else". In a hospital, the choice is "use our services or die". I'm a little more inclined to be forgiving in that situation.
        • In a restaurant, the choice is "eat here or eat somewhere else". In a hospital, the choice is "use our services or die". I'm a little more inclined to be forgiving in that situation.

          1) Not every patient who enters the Emergency Department is dying.

          2) In my example, there are no restaurants that do not suffer from "dine and dash" patrons. The same is try for hospitals. There are no magical hospitals that get paid for 100% of the services they render.

  • Nothing _that_ new... (Score:3, Informative)

    by imsabbel ( 611519 ) on Saturday November 10, 2007 @04:01PM (#21308547)
    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.

    • Re:Nothing _that_ new... (Score:4, Informative)

      by ceoyoyo ( 59147 ) on Saturday November 10, 2007 @05:24PM (#21308963)
      Not quite. Higher gradients give you faster imaging. Higher fields give you better signal to noise. Better signal to noise can allow you to actually use those higher gradients without ending up with a big mess of noisy pixels.

      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.
      • There are hard limits to resolution. You mentioned one in the SNR issue. But you signal average till kingdom come to get around that. Another issue is that at very small voxel sizes, diffusion becomes important, and you get blurring in your image as a result. Understanding how important this is depends on the tissue type, of which I am not an expert (I am not a clinical MRI guy, but a research and development type). BTW, the SNR enhancement from stronger fields goes roughly as the square of the field,
  • I wonder if this will open up MRIs to those of us who currently cannot have them done. I have a metal-mesh plate in my skull due to an open brain injury, and my doctors repeatedly cautioned that I can never, under any circumstances, undergo an MRI. The electro-magnets are apparently so powerful that they have the ability to rip the plate right out of my head.

    So, perhaps now that they've found a way to get around the necessity of humongous electro-magnets, people like me will be able to take on an MRI wit

    • Re: (Score:2)

      by IvyKing ( 732111 )
      The system from TFA may not be of much help to you. For one, the system still uses a fairly power pre-polarization field which could interact with your plate. Another problem is that the plate could interfere with the excitation and readout fields (this could be minimized by changing orientation).


      Your doctors were doing you good service about the warnings with respect to MRI.

  • The whole proclaimed need for communications surveillance and arbitary invasions of ideological nations is because there's not a practical warning and defense system against some jackass carrying a bomb.

    Now, there is.

    If small, portable MRIs can be mass produced, we could have simple scanners that you step through in key areas, and quickly identify if you have explosives on your person. There's no need for trying to figure out who might try and blow someone or something up. Instead, we'll just be able to ca

  • FTA: "The magnets ... draw most of their power from supercooled helium"

    What utter bull, When are the writers about scientific subjects going to go to school? This is knowledge I'd expect every Year 12 student to have so that they do not eject this kind of howler.

    Ditto, of course to the dim nitwits who took the iron things into the MRI scanning room. If the US is going to try to keep its preeminence as a world power it had better start building a few new schools, and pay the teachers sufficient to get

  • I gave this issue some thought tonight. If a quality MRI machine costs say $100 and weighs less than 10 pounds, what new technologies would we see?

    I couldn't come up with very much. Maybe you can? Could you make a scanner that scans a whole book at once with an MRI, since it could take a 3D image of the insides of the book and then split it into pages with software? I guess it would have to detect locations where there is ink by looking for those molecules?
  • Unfortunately, it's just a picture of the researcher's thumb.

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