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China Medicine Science

First Images of a Heart Injected With Liquid Metal 115

Posted by Soulskill
from the that's-pretty-metal dept.
KentuckyFC writes "The early symptoms of many diseases show up first in the smallest blood vessels, but imaging the fine structure of these vessels is a tricky problem for medics. The most common way is to inject them with a contrast agent and use x-ray tomography to create a 3D image of their structure. This shows problems in the large vessels but not smaller ones. The problem is the lack of contrast. Conventional contrast agents are based on iodine, which has a high electron density and so better absorbs x-rays than other atoms. But a better solution would be to use a higher density fluid, such as a liquid metal. The obvious fears associated with toxicity and so forth mean this has never been tried. Until now. A team of Chinese biomedical engineers have created the world's first images of a pig's heart injected with gallium. This has a melting point of 29 degrees C, so it's a liquid at body temperature. And the results show the detailed structure of the tiniest blood vessels, revealing capillaries just 0.07 mm in diameter. That's significantly more detailed than is possible with iodine-based contrast agents. An important question is whether this technique will ever be possible in humans. The Chinese team seems optimistic. They say gallium is chemically inert, non-toxic to humans and can be injected and sucked out without leaving a residue. 'It suggests the possibility for localized in vivo vascular-enhanced radiological imaging in the near future.'"
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First Images of a Heart Injected With Liquid Metal

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  • by etash (1907284) on Friday December 06, 2013 @11:46AM (#45619549)
    "what could possibly go wrong" post

    or the "not invented here" post.
    • by Anonymous Coward

      "what could possibly go wrong" post

      or the "not invented here" post.

      As opposed to what could possibly go wrong (and does) thousands of times a year in operating rooms?

      Advanced medicine doesn't advance in the face of unnecessary skepticism.

      • Glad you feel that way. You'll be signing up to be one of the first test subjects, right?

        • by Phics (934282) on Friday December 06, 2013 @12:54PM (#45620229)

          They have a term in medicine called "contraindication". Basically, when there are contraindications, (downsides), the risks and benefits of a treatment are weighed, and if the benefits outweigh the potential complications, it might be worth trying regardless. Test subjects sign on for trials because they feel the risks are acceptable. The AC may not fall into this category, but that doesn't mean (s)he's wrong if they don't choose to 'sign up' to have this done unnecessarily. I wonder if you'd have had a similar reaction if someone suggested injecting a fungus into the bloodstream... sounds horrifying, but how many lives has penicillin saved?

        • I would if that would have even a tiny possibility of saving my life.
          Just as well, I would volunteer for most tests involving cybernetic implants.

          People are different and they have different goals. Some are willing to die for democracy, others for stray dogs, others for medicine advances.

        • When you have a 100% chance of dying without a procedure vs a 90% chance with, then yes, I'll be the first.

      • by icebike (68054)

        Advanced medicine doesn't advance in the face of unnecessary skepticism.

        On the contrary, just about ALL skepticism is both necessary and warranted, until proven otherwise.

    • Well slashdot reads my mind, because the first "you might like to read" right below TFS is "US Executions Threaten Supply of Anaesthetic Used For Surgical Procedures"

      So nothing will go wrong. China produces enough "volunteers" yearly to run a few experiments. They might get an offer for redemption for putting their lives on the line for the good of the people.

    • That can pass though bio sensor with living tissue

  • by ganjadude (952775) on Friday December 06, 2013 @11:53AM (#45619631) Homepage
    I am intrigued. I mean is this the start of the T-1000???
  • But what if it does leave a residue? And what if that residue - chemically inert, apparently - remains in the body indefinitely? And what if you then go outside in a cold day, and that residue drops below 29 C in your extremities?

    • by XMark3 (2979399) on Friday December 06, 2013 @11:56AM (#45619661)
      I think at that point you turn into Wolverine.
    • by mark-t (151149)
      You may want to consider the fact that having a temperature of only 29C would constitute the onset of very severe hypothermia (mild hypothermia starts at about 34C or so). Not that I think this is a good idea, but a person with even a moderate awareness of their surroundings should have plenty of warning that this is happening.
      • by H0p313ss (811249)

        My understanding is that's the "core" temperature, and that extremities drop below that all the time, but I have not researched this at all.

      • by djmurdoch (306849)

        29C in your heart would be a big problem, but 29C in your extremities (which the GP was talking about) is not that unusual. Don't you know anyone who has cold hands or feet sometimes?

      • by fnj (64210)

        Er, you might want to consider that the body is hardly one fixed tempoerature, especially if you don't have textbook perfect circulation. If the human core temperature is 37 C, that does not mean all the fingers and toes are 37 C. I don't find it far fetched at all that extremities could be at or below 29 C. If you live long enough, and get stuck in some hideous northern climate, you will know exactly what that is like, even without metal freezing in them.

      • I can assure you in Canada your extremities would go well below that in winter.

        • by mark-t (151149)

          I come from Edmonton, Canada... I'm well acquainted with just how cold it gets up here.

          And if your extremities are that cold, then you can be damn sure that frostbite is setting in. We're not talking about topical skin temperature here... we're talking about the temperature of what's underneath, and underneath your skin even at the extremities won't ordinarily deviate from core temperature more than about a couple of degrees. Any more than that and you have a problem.

          If you are wearing proper gear fo

          • by Smauler (915644)

            And if your extremities are that cold, then you can be damn sure that frostbite is setting in. We're not talking about topical skin temperature here... we're talking about the temperature of what's underneath, and underneath your skin even at the extremities won't ordinarily deviate from core temperature more than about a couple of degrees. Any more than that and you have a problem.

            Frostbite is your tissue freezing. You can't get frostbite until the temperature of your fingers/toes/whatever drops below

            • by mark-t (151149)
              The surface of the skin may be freezing during mild frostbite, but underneath the skin it will still be fairly warm.
  • Gallium = Sticky (Score:5, Interesting)

    by Iskender (1040286) on Friday December 06, 2013 @11:57AM (#45619671)

    At least according to http://theodoregray.com/periodictable/Elements/031/index.s7.html [theodoregray.com] gallium and at least some of its alloys are really sticky, leaving residue on most anything. "Unfortunately, it stains your hands and is hard to get off, so I don't recommend it. In fact, it stains or sticks to just about anything, which is very irritating because it would otherwise make a very nice substitute for mercury where a liquid metal is called for."

    I've used one of those gallium-containing fake-mercury thermometers myself, and after a few uses the liquid metal got stuck to the glass tube, and it never worked again. They could have made some better alloy of it or something, but that's not mentioned in the abstract, at least.

    (Also, someone is actually using Medium? Impressive, I was compelled to use it for a course, and it was the most dead "social network" I've ever seen.)

    • Well, then this is a feature, not a bug. The patient already set up for another contrast exam. They should patent it.

      Actually, for clinical purposes it's not all that useful to see tiny blood vessels. If you have a blood clot in a tiny artery, no big deal. It's the large supply arteries that put one in danger. We can already assess areas with poor perfusion with a couple of other technologies.

      As a research tool, it may well be useful.

      • by Rob Riggs (6418)

        Well, then this is a feature, not a bug. The patient already set up for another contrast exam.

        And can never pass through a metal detector unmolested...

      • Actually, for clinical purposes it's not all that useful to see tiny blood vessels. If you have a blood clot in a tiny artery, no big deal. It's the large supply arteries that put one in danger. We can already assess areas with poor perfusion with a couple of other technologies.

        As a research tool, it may well be useful.

        We can assess perfusion defects in a fairly poor way with current tech. But they suck. Spect is absolute shit, unless you happen to own a nuke scanner, then you probaby disagree with me. Be it's called "Un-clear medicine" for a damn good reason. Gadolinium perfusion in MRI is better, but to get the needed temporal resolution, it's not great. Still better than nuke med. Plus the FDA still doesn't approve of its use. Even though it gets used for perfusion and late enhancement in cardiac mri thousands of times

      • In my day job I write medical imaging software, I'm not a radiologist though having seen tens of thousands of studies I think the image on the right was cherry picked. (Might be this immediately disqualifies my opinion, but something isn't right here : ) It almost looks like they didn't inject any iodine at all - The window levels are different, they both look like they came from different modalities with different slice thicknesses. The PDF has a lot of information about power levels, but no DICOM, no deta

    • Yep. Between the stickiness, the quick formation of an oxide "skin", and the expense, it's not nearly as much fun as mercury. Mercury really is a wonder material -- it's just a darn shame about that cumulative neurotoxicity.

      So, for liquid metals, so far we have:

      Mercury -- low-melting, extremely dense, fairly cheap, fairly unreactive, high surface tension/nonwetting, but with a high vapor pressure and serious toxicity issues

      Gallium-indium alloys -- somewhat low-melting, medium density, very low vapor pressur

    • Re:Gallium = Sticky (Score:4, Informative)

      by ridgecritter (934252) on Friday December 06, 2013 @01:55PM (#45620771)

      It is that. I've seen it stick to Teflon and graphite components. It coats glass and silicon wafers with a nice mirror surface.

      Lowest melting nontoxic liquid metal I've heard of is Galinstan, a eutectic alloy of gallium, indium, and tin, melts around -19C. http://en.wikipedia.org/wiki/Galinstan [wikipedia.org]

    • A while back there was research out of MIT for new coatings to keep substances sticking to the walls of bottles. http://www.fastcoexist.com/1679878/mits-freaky-non-stick-coating-keeps-ketchup-flowing [fastcoexist.com]. How about something like this? For the thermometers. Not sure I want that stuff in my heart either.

      • They usually use a coating of Gallium Oxide... it's clear enough for the purposes, and the Gallium alloys they use in the thermometer won't stick to it.

        That said, the Gallium-based thermometers aren't of much use in extremely cold areas... Gallinstan freezes at -19'C, and I've lived in areas where it can get to -55'C (before the wind chill kicks in).

  • My eyes! They may need to perform this trick on them to find all the capillaries that just burst...

    • On my mobile device, half the text is under the X-rays, looking like some bizarre part of it.

      Needlessly using some complicated HTML generator that tries to control layout down to the atom FTL.

      • by X0563511 (793323)

        My favorite are sites that load a form or image in a "window" that tries to anchor to the center of the screen. Can't read it 'cause it's 1-inch wide? Zoom in... oh wait, NOPE! It moves itself to the right side expanding the page, and you get to play "chase the AJAX" - the only way to win is not to play.

  • by Anonymous Coward

    Not surprisingly the improvements here are not just restricted to the visual field. If Gallium provides a lower level detail, it would also reveal lower level heart wall abnormalities that usually requires the patient to be subject to a MUGA scan or resting Thallium study to reveal smaller perfusion defects. These tests can occur post-angiography (heart cath) exposing the patient to more dye increases the rate of kidney failure and kidney malfunction following radionuclide dye procedures. Additionally,

  • So what happens to the nervous system when exposed to liquid metal? The brain and muscles that work off electrical impulses. Wouldn't liquid metal interfere with this?

    • by djmurdoch (306849)

      Blood is quite conductive as well, being salty water with a bunch of other junk in it.

      • Right, but what about resistance (ohms law) of blood vs gallium? Does it matter?

        • by AK Marc (707885)
          Nope. The nervous system is insulated, and there would be preferred paths over shorter distances than through the blood.
    • by jonnythan (79727)

      Electrical impulses, but not actual electricity. You of course realize the body is highly conductive to electricity already.

  • I want to see more about the pig on whom the experiment was done.
  • How do they suck the metal back out after it's in every tiny blood vessel of a heart? Maybe most of it stays cohesive enough to suck out in one draw, but surely as blood vessels collapse under the suction, bits and pieces of the liquid metal will break off and remain within the blood vessels. How do they get that metal out?

    Does it flow through capillaries?

    • they don't

      this idea is stupid

    • by AK Marc (707885)
      How do they suck the waste out of the blood of someone with kidney failure? It's a solved problem. Why is slashdot filled with people who publicly announce; "I'm too stupid to solve this problem, so that's proof it's impossible" (or phrase questions with that implication, even if they immediately assert it was "just an innocent question".

      Though the question was about imaging only, so removing it wouldn't be an issue. You don't, the pig dies, you get more gallium and sell some bacon.
      • by hawguy (1600213)

        How do they suck the waste out of the blood of someone with kidney failure? It's a solved problem. Why is slashdot filled with people who publicly announce; "I'm too stupid to solve this problem, so that's proof it's impossible" (or phrase questions with that implication, even if they immediately assert it was "just an innocent question".

        Why is slashdot filled with people who publicly claim that the solution to complex problems is already solved because there are solutions to other problems that seem similar on the surface?

        Dialysis is not "sucking it out" - Dialysis is carefully filtering it out -- which seems at odds with TFA's assertion that the gallium can be easily sucked back out.

        Though the question was about imaging only, so removing it wouldn't be an issue. You don't, the pig dies, you get more gallium and sell some bacon.

        Removing it is not an issue as long as you don't care about the creature that you're imaging surviving, which is usually not the case in diagnostic imaging. T

        • by AK Marc (707885)

          Why is slashdot filled with people who publicly claim that the solution to complex problems is already solved because there are solutions to other problems that seem similar on the surface?

          Because filtering blood is a solved problem. The only (small) difference is what the filters are tuned for.

          Removing it is not an issue as long as you don't care about the creature that you're imaging surviving, which is usually not the case in diagnostic imaging. TFA suggests that it could be expanded to humans.

          You solve problems one step at a time. It's pointless to solve for removal when the imaging isn't any better. So you test imaging first. Then you work on the next problem. If someone hasn't solved every piece of a puzzle, we should assume it's impossible?

    • by rubycodez (864176)

      they have a nurse with DSL

  • Gallium Metal (Score:5, Informative)

    by Artagel (114272) on Friday December 06, 2013 @12:29PM (#45619955) Homepage

    Having worked with gallium, it is not the easiest metal to work with. It forms oxides easily on its surface, and when these oxides combine with the metal, the metal can stick to metals and glass quite easily. Gallium has been used to back mirrors for that reason.

    For those wondering, just because it melts easily, does not mean it has any vapors. Unlike mercury, it has a very high boiling points and has essentially zero vapor pressure at temperatures that can be tolerated by people. As for non-toxic, as far as I know it is not poisonous in reasonable quantities, but neither is it generally recognized as safe (GRAS). Six-nines gallium is probably what to use (99.9999%), as Five-nines gallium (99.999%) usually has signifcant mercury levels in the remaining portion.

    It supercools very nicely in plastic containers, and once melted will stay liquid at room temperature for quite a while. It expands upon freezing, like water, and often develops a distinctive cracking pattern when solidifying.

    It will eat aluminum instantly. Certain stainless steels are fine for a while, but iron (not plain steel), berylium, tungsten and the like are other metals you can use with it and not have problems with dissolving part of it.

    It is a blast, and you can buy small quantities of it from Amazon.

  • The name is clearly unacceptable. Change it from "gallium" to "freedomium" .

    (Yes, you language pedants, that is the origin of the name)

  • Never been tried? (Score:5, Interesting)

    by TheCarp (96830) <sjc AT carpanet DOT net> on Friday December 06, 2013 @12:49PM (#45620177) Homepage

    The problem is the lack of contrast. Conventional contrast agents are based on iodine, which has a high electron density and so better absorbs x-rays than other atoms. But a better solution would be to use a higher density fluid, such as a liquid metal. The obvious fears associated with toxicity and so forth mean this has never been tried.

    So my mother was an X-Ray technition for 25 years, and was trained in the 70s. In fact, metals, if not this kind of "liquid metal" have not only been tried, but used. In fact, when she was working back in the 90s, she used to say that soft tissue x-rays back in the 50s were much sharper because of the better contrast they had.

    Better....because it contained thorium. While it made amazing x-rays, it turned out to not be so good for the patients. Turns out those "harmless" alpha decays are a lot less harmless when they happen inside your body.

    I never really looked up the specific contrast before, apparently mom got her decades wrong, but it was history for her too so that isn't too surprizing: http://en.wikipedia.org/wiki/Thorotrast [wikipedia.org]

    • An aqueous suspension of thorium dioxide is in no way, shape or a form a "liquid metal". It would be like calling that aqueous suspension of iron oxide (otherwise know as "red house paint") a "liquid metal".

      • by TheCarp (96830)

        yes I know. Normally when you see quotes and qualifiers its a good indication someone is playing a bit fast and loose with a definition. If I wasn't aware of that I would have just called it a liquid metal and saved myself some characters.

    • The entry for "Alpha Particles" was updated from "Harmless." to "Mostly Harmless." quite some time ago. Because it is... AS LONG AS the emitter is *OUTSIDE* the body.

      An alpha particle is going to steal electrons from the first molecule it comes in contact with, and become a helium atom. If you're exposed to alpha radiation from the outside, it's going to hit and react with the layer of already dead skin cells called the epidermis.

      So yes, as long as you don't swallow, inhale, inject, or otherwise insert th

  • Is the gallium heart Ig Nobel material or just an element like a golden heart?

  • Melamine laced pet food and baby formula... Awesome... can't wait to try it!
  • They can't be serious about anything except getting press attention. Gallium is sticky, not all that unreactive, and immiscible with water-based fluids. So, when you inject it, it displaces blood (thus cutting off oxygen to the tissues it perfuses), it gets lodged wherever it goes, and it almost certainly leaches into the surrounding fluids fairly swiftly as chloride ions and oxidizing species attack it. And ionic gallium isn't that non-toxic, as I recall.

  • Look up "Gallium Scan". It is typically used to help determine if a cancer has metastasized.

    You get injected with a gallium solution, and then wait two days while the radioactive ions collect in bones and tissues. When it's time for the scan, you lay on a table that effectively holds a body-sized film. The "scan" involves you laying still for 30 minutes while the film is exposed to your body.

    Each time I had this done, I was told to stay away from small children for a week after the procedure.

    • From the Wikipedia [wikipedia.org] article

      The body generally handles Ga3+ as though it were ferric iron (Fe-III), and thus the free isotope ion is bound (and concentrates) in areas of inflammation, such as an infection site, and also areas of rapid cell division. Gallium (III) (Ga+3) binds to transferrin, leukocyte lactoferrin, bacterial siderophores, inflammatory proteins, and cell-membranes in neutrophils, both living and dead.

      This relatively nonspecific gallium binding allows sites with tumor, inflammation, and both acute and chronic infection to be imaged by nuclear scan techniques.

      Gallium is used because it is relatively 'sticky'. A useful trait for radionuclide scans (where the actually amount of metal is tiny), also useful if you want to make high resolution pictures of a soon-to-be-bacon animal. For in vivo use on organisms planning on hanging around this mortal coil for a while, perhaps not so much.

  • 1) Absorption of the xray beam is not just based on a material's electron density. The contrast media we use today have a k-shell energy in the mid 30 kev which causes a sharp increase in the amount of absorption due to the photoelectric effect proportional to compton scatter. This means they have a higher absorption at these energies than their atomic number would indicate. Gallium's atomic number is lower than iodine's and its k edge is at 10 kev rather than in the 30s. I find it hard to believe that i

  • by pz (113803) on Friday December 06, 2013 @01:39PM (#45620641) Journal

    They say gallium is chemically inert, non-toxic to humans and can be injected and sucked out without leaving a residue.

    Doing even the most cursory of searches on gallium and reading through the Wikipedia entry (http://en.wikipedia.org/wiki/Gallium) would suggest that gallium is not chemically intert, may not be non-toxic to humans, and given that extremities can easily get cold enough to drop below the freezing point of gallium, I'd have to say that it might rather well leave a residue, forget about the stickiness others have reported.

    Yea, that'd be great: inject liquid metal, have it thicken and solidify in your feet and fingertips because you step outside on a brisk day, giving you the equivalent of massive frostbite. No thank you.

    There are growing numbers of Chinese researchers in my field (neuroscience) and their results always need to be taken with an extra-large grain of salt. It looks like the same is true here.

  • by Jeremy Erwin (2054) on Friday December 06, 2013 @01:56PM (#45620779) Journal

    That's an unusual choice.I would have used Mercury, or hot molten lead.

  • When we can trust the Chinese to not use lead in children's toys [google.com] I think we should take a look at this gallium thing.

  • by Chewbacon (797801) on Saturday December 07, 2013 @10:48AM (#45626675)

    I'm relatively new to the cath lab, but Iodine-containing agents typically get the job done as far as diagnosing coronary blockages. In my lab, we do nuclear scan for evaluating perfusion even before we decide to do an angiogram (albeit we sometimes do it anyway, but that becomes an insurance battle). A worthwhile advantage would be lower risk of renal failure (not mentioned in the article). While few patients with healthy or even mediocre kidneys end up having problems, it's always a concern with those of less renal function and will sometimes mean not doing an elective cath.

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