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Wirelessly Powered Medical Implant Propels Itself Through the Bloodstream

Posted by Soulskill on from the boy-it's-dark-in-here dept.

cylonlover writes "With the wait still on for a miniaturization ray to allow some Fantastic Voyage-style medical procedures by doctors in submarines, tiny electronic implants capable of traveling in the bloodstream show much more promise. While the miniaturization of electronic and mechanical components now makes such devices feasible, the lack of a comparable reduction in battery size has held things back. Now engineers at Stanford University have demonstrated a tiny, self-propelled medical device that would be wirelessly powered from outside the body, enabling devices small enough to move through the bloodstream."

37 comments

  1. What do you call... by Overzeetop · · Score: 4, Insightful

    What do you call a small, disabled/inert object flowing through your circulatory system? A stroke waiting to happen.

    --
    Is it just my observation, or are there way too many stupid people in the world?
    1. Re:What do you call... by Baloroth · · Score: 1

      Given that the device will be capable of self-propulsion with the external power source, it should be relatively easy to guide the unit to a specific location for easy extraction. Or have it burrow into the body in a location such that it doesn't move (if the device needs to be reused later on or simply cannot be removed), as creepy as that thought is. I imagine approval for medical usage will require a demonstration of such capability prior to use, as well as a demonstration that the device won't accidentally cause a stroke or other damage during operation. You could possibly even make the device degradable, so it would harmlessly disintegrate into trace (non-dangerous) elements in the bloodstream after a few hours.

      --
      "None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
    2. Re:What do you call... by jimbolauski · · Score: 2

      What happens when shit goes wrong and the device loses power, it will wind up in the lungs (Pulmonary Embolism) or brain (stroke). What fail safe could there possibly be to stop an object from moving freely without stopping the flow of blood around the object.

      --
      Knowledge = Power
      P= W/t
      t=Money
      Money = Work/Knowledge so the less you know the more you make
    3. Re:What do you call... by timeOday · · Score: 1
      A stroke is in the brain. There's no way this would get through the blood-brain barrier.

      If something like this did conk out somewhere in the body, perhaps you could prevent it from circulating with an external magnet.

    4. Re:What do you call... by timeOday · · Score: 2

      Applications aside for the moment, I am absolutely amazed that the propagation of RF energy through the body was so wrongly understood previous to this. With all the types of imaging and treatments that involve radiation, from x-rays to airport mm wave scanners to radiotherapy, how can it be nobody had tested frequencies in this range? I'm sure the cellphones-cause-cancer crowd will be fascinated to hear that the optimum frequency for tissue penetration is around 1 GHz, which just happens to be in the middle of cellphone spectrum.

    5. Re:What do you call... by Anonymous Coward · · Score: 0

      What fail safe could there possibly be to stop an object from moving freely without stopping the flow of blood around the object.

      I'm not a doctor but... make the object porous?

    6. Re:What do you call... by Baloroth · · Score: 1

      Make it magnetic, maybe? The device fails, you stick a moderately powerful magnet near its location, it's attracted to the magnet and doesn't shift to the lungs or brains. Or perhaps you make it small enough that it won't even get stuck at all (I'm not a doctor or biologist, so I'm not sure how small it would have to be and/or if that is at all practical). Worst case scenario, you design it so it will block bloodflow and not move freely if it fails: a few minutes of a lack of bloodflow to most parts of the body is not very dangerous (basically, so long as it isn't the lungs, heart, or brain). Or you could make it have a latching mechanism (imagine some kind of spikes that shoot out and grab the insides of the veins if it loses power) that triggers automatically if it fails. It won't block bloodflow, and it won't move (again, not sure if practical, just an idea).

      The story is only about a method for powering the device, there are a ton of practical problems to solve before you make such a device in actuality.

      --
      "None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
    7. Re:What do you call... by Metabolife · · Score: 1

      Give it a rotating saw, it will cut right through the cholesterol. Hell, when they get cheap enough, put them on patrol searching for future blockages.

    8. Re:What do you call... by Fned · · Score: 1

      Pish tosh, simply have tiny electromagnets, holding back, spring-loaded barbs. The moment the device loses power, it immediately anchors itself, implacable, in the blood-vessel walls! Why, any child could have come up with this, both simple, and elegant, solution!

    9. Re:What do you call... by Anonymous Coward · · Score: 0

      Yeah, but Palladium poisoning is a bitch.

    10. Re:What do you call... by izomiac · · Score: 3, Informative

      The blood brain barrier refers to the tight junctions between endothelial cells in the capillaries of the brain. With age these junctions loosen. Here is a scanning electron microscope picture of such a capillary.

      A stroke generally involves a macroscopic embolus getting stuck in an artery in the brain. As-in a pathologist can often physically find it during an autopsy (I once heard of one that showed how one fit together with a thrombus in the leg much like two pieces of a jigsaw puzzle). The scale of the BBB and a thrombus is completely different.

      IOW, a stroke involves blocking an artery, which happens long before it reaches the capillaries and BBB. You can contrast this with a pulmonary embolus which is usually a shower of small clots blocking smaller blood vessels in the lungs (although you can get things like a saddle embolus where a large clot blocks both pulmonary arteries... it's very bad).

    11. Re:What do you call... by es330td · · Score: 1

      It won't block bloodflow

      If plaque builds up in arteries, why would it not build up on this stationary object in a blood vessel?

    12. Re:What do you call... by timeOday · · Score: 1

      Interesting, thanks.

  2. oh no by formfeed · · Score: 3, Funny

    First thing that came to my mind was the Breeding cycle of the black helicopter

    I should get out more

    1. Re:oh no by Eponymous+Hero · · Score: 1

      the most important fact that everyone seems to be missing is the engineer's name is Poon.

      --
      insensitive clod overlords obligatory xkcd car analogy russian reversals whoosh pedant fanbois ftfy in 3...2...1..PROFIT
    2. Re:oh no by axlr8or · · Score: 1

      Hey, thanks for the link. Does DEET work on these things?

    3. Re:oh no by formfeed · · Score: 1

      Hey, thanks for the link. Does DEET work on these things?

      No. But DDT. (which has been outlawed by ... the governement)

  3. Cool but ... ? by RNLockwood · · Score: 3, Informative

    What's that word I'm looking for? Ah, yes, embolism. That's what it's called if it get's stuck in too small artery.

    --
    Nate
    1. Re:Cool but ... ? by Eponymous+Hero · · Score: 0

      arteries and veins are the largest blood vessels. you must be thinking of arterioles, venules or capillaries, which obviously are not what these devices will be programmed to travel in. thanks for not RTFA!

      --
      insensitive clod overlords obligatory xkcd car analogy russian reversals whoosh pedant fanbois ftfy in 3...2...1..PROFIT
    2. Re:Cool but ... ? by houstonbofh · · Score: 1

      And when the power cuts out? Sorry about that stroke...

    3. Re:Cool but ... ? by Anonymous Coward · · Score: 0

      Of course, because the scientists behind this couldn't possibly have thought of that already, could they? No, once again, it's down to a lone Slashdot reader to bring us out of the dark and into the light to see the error of our ways! Hallelujah!

    4. Re:Cool but ... ? by RNLockwood · · Score: 1

      I did RTFA (as best I could following eye surgeries). Both of the links. Twice now. It's a cool idea but nothing in press release about keeping the device from getting stuck, retrieving it, or bucking the blood flow It won't ever get stuck? Blood flow will never exceed its speed? No one will ever make an error operating it? The OR won't ever have a power glitch? My code always works the first time? Slashdot commenters don't ever make ad hominem arguments?

      --
      Nate
    5. Re:Cool but ... ? by Eponymous+Hero · · Score: 1

      found this link on the same page as TFA: http://www.gizmag.com/biological-fuel-cells-use-blood-sugar/19261/

      --
      insensitive clod overlords obligatory xkcd car analogy russian reversals whoosh pedant fanbois ftfy in 3...2...1..PROFIT
    6. Re:Cool but ... ? by Eponymous+Hero · · Score: 1
      if you did read it, i couldn't tell. but then again maybe i thought a little more about what i read.

      these things are designed to travel through arteries. by default they would have to be small enough to pass through the smallest of arteries. you're assuming Poon overlooked that minor detail? really? i didn't think so, so i gave you the benefit of the doubt and still couldn't see your viewpoint. occam's razor indicated you probably had not read it.

      from TFA, emphasis mine...

      Poon's research could finally enable the development of medical implant s capable of traveling through the bloodstream to deliver drugs to a specific area, perform analyses, and maybe even zap blood clots or remove plaque from arteries .

      sorta like the reason why nobody ever got stuck in the Lazy River at Wet'N'Wild (the only good thing the Vegas strip ever had, imho). they weren't just pieces of detritus. they could control their movement, they could remove obstacles in the way (zap blood clots, remove plaque). like this implant. and if someone ever did get stuck in the Lazy River, there were always plenty of other people (other implants) to free the stuck person.

      worst case scenario - nothing prevents it from being stuck, and no other implants are around to free it - it could be designed with a self-destruct mechanism to break it up into smaller pieces (like ultrasound to break up kidney stones). maybe the ultrasound method itself could work if it's improved. maybe the researchers should be given more benefit of the doubt after having gone this far with it. you didn't just swoop down from your armchair and out-think an engineer's entire career in 5 seconds.

      "There is considerable room for improvement and much work remains before these devices are ready for medical applications ," said Poon. "But for the first time in decades the possibility seems closer than ever."

      --
      insensitive clod overlords obligatory xkcd car analogy russian reversals whoosh pedant fanbois ftfy in 3...2...1..PROFIT
  4. ditch the batteries by L3370 · · Score: 2

    While we wait for nanobatteries, we could ditch the battery supply altogether and use external magnetic forces to propel it through the vessels. Maybe an MRI unit with some tweaks? Then harness the energy of rushing/flowing blood to power the sensors taking readings.

    1. Re:ditch the batteries by Anonymous Coward · · Score: 0

      That's what TFA is about... and the summary mentions it...

  5. Re:Frosty implants by Jeremiah+Cornelius · · Score: 2

    Tiny, self-propelled medical device, moving through the blood-circulatory system?

    We men of-a-certain-age, DEMAND these include RAQUEL WELCH!

    --
    "Flyin' in just a sweet place,
    Never been known to fail..."
  6. It it just a model? by Extremus · · Score: 2

    I gave a look at the article, but didn't find any mention to a working prototype. Since the device requires a new model of human tissue to be right, it will be nice if they could test the model first.

  7. Folks just RTFA before the embolism ! by ACK!! · · Score: 1

    I mean the article says that this thing is a long way off before being ready for medical applications in the field.
    So, before we freak out and sit out pacemakers next to the microwave and everything, we should take a deep breath and calm the fuck down.
    They realize there are things to work out but for now the headline should state the scientists think it is now feasible and probable.
    I think we should all return to make jokes about Raquel Welch and the scientist whose name is Poon.

    --
    ACK /ak/ interj. 2. [from the comic strip "Bloom County"] An exclamation of surprised disgust, esp. i
  8. Does it come with... by wisebabo · · Score: 1

    ... a tiny Raquel Welch?

    Anyone know if there's going to be a remake of "Fantastic Voyage"? Even though the Futurama spoof was more scientifically accurate (sentient worms?) I found it to be less emotionally thrilling because the characters lives weren't really at stake.

  9. Unknown GHz attenuation? by Anonymous Coward · · Score: 0

    I have trouble buying that the attenuation of a human body at low GHz frequencies wasn't known. The Larmor frequency of a 2 Telsa MRI is around one GHz, so attenuation would have to be low in order without tissue thickness throwing in too much noise for a clean signal.

  10. Video related. by Anonymous Coward · · Score: 0

    http://www.youtube.com/watch?v=7AWfzy7wdv4

  11. Proof positive I am no genius by erroneus · · Score: 1

    The use of wireless power as the means to power tiny medical devices is a head-slapping "obvious" in my opinion... except for one thing... it never occurred to me though I am aware of wireless power and aware of the battery size (power density) problems of batteries.

    In short "Why didn't *I* think of that?!" The answer to the rhetorical question is that I'm not such a genius at all...

  12. Great! by wcrowe · · Score: 1

    How soon before we can turn this into some sort of weapon?

    --
    Proverbs 21:19
  13. It's a start, not a finished application by Anonymous Coward · · Score: 1

    I saw the project presented at ISSCC (International Solid State Circuits Conference) earlier this week. It really is basic research into feasibility rather than an attempt at a true implantable device and at that level is pretty cool.

    The device receives both power and control from an external transmitter. It has two modes of locomotion: magnetohydrodynamic (think Red October instead of Fantastic Voyage) and another where it pivots on different points to pull itself forward. Both modes were demonstrated in a tank of fluid and seemed to work fairly well..

    The actual device, including antenna area, was shown in comparison to a US penny. It was about the size of Lincoln's head, hence way too big for a real design. However, the size was chosen more for convenience (it's nice to be able to see the prototype without a microscope) and it was pointed out that scaling it down would have a positive affect on it's power consumption and maneuverability.

    I wouldn't expect anyone to turn this into a real application anytime soon. As one questioner at the conference pointed out, navigating the blood stream is a lot harder than a still tank of water. Still, it's a start on something that could be very useful some day.