5 ms·

It's a cool idea, but let's not give short shrift to the MRI downside. MRIs are a big deal in today's medical world. Not being able to get one, depending on cir

It's a cool idea, but let's not give short shrift to the MRI downside. MRIs are a big deal in today's medical world. Not being able to get one, depending on circumstances, can present anything from a mild inconvenience to a significant challenge. Especially if it's because of some piece of metal you elected to have implanted. I type these words with a (non-elective) series of metal prostheses implanted in my hand and wrist. Luckily, I don't set off metal detectors unless they're turned to extremely high sensitivities. But MRIs are out. I don't want to get into TMI detail, but let's just say that I have an ongoing medical condition that makes the inability to get MRIs a big setback. Tread carefully with this stuff. Look before you leap.

icegreentea 15y ago
Though it would seem that removing the magnet wouldn't be too much of a problem. I mean, it should show up under flouroscopy, and failing that, I guess you could mark the spot with tattoos with when get them implanted. Would still be a headache though.
AkThhhpppt 15y ago
There's a reason I have a Rod of Asclepius and "DO NOT MRI" tattooed on my wrist. Apparently it's quite possible to go through an MRI with implant intact, so long as the techs know about it. The inventor of these implants' advice about MRIs can be found here: http://www.stevehaworth.com/wordpress/index.php/welcome-from-steve-haworth/magnetic-faq http://www.stevehaworth.com/wordpress/index.php/welcome-from...
- jonnathanson 15y ago
  That is good to know. Thank you for the clarification. I'm glad the inventor took this into consideration.
- jpdoctor 15y ago
  > There's a reason I have a Rod of Asclepius and "DO NOT MRI" tattooed on my wrist. You realize there are other large magnets in the world besides those for MRIs?
  - AkThhhpppt 15y ago
    Yes, but how many large magnetic fields does one gets stuck into while unconscious that _aren't_ MRIs? Besides, I've been exposed to serious magnets; the inverse cube law is my friend. Plus, even when I did come close to a strong magnet, all that happened was my implant flipped ends. In my finger, yes, but it wasn't painful (my implant is a cylinder, about as tall as it is wide; a disc magnet would have been much worse).
    - jpdoctor 15y ago
      > Yes, but how many large magnetic fields does one gets stuck into while unconscious that _aren't_ MRIs? If by "unconscious" you mean asleep, not many. If by "unconscious" you mean unaware, plenty. Try walking past these in a lab: http://www.youtube.com/watch?v=J2PDAnKEu9M http://www.youtube.com/watch?v=J2PDAnKEu9M FYI: Neodymium magnet strength is of order 1T, same as MRI.
      - AkThhhpppt 15y ago
        See where I mentioned the implant "rolling over"? That was caused by someone waving a stack of over 20 of these type of neodyms (http://www.magnets2buy.com/acatalog/neodymium-discs.html http://www.magnets2buy.com/acatalog/neodymium-discs.html) within an inch of my finger. Those are so powerful that splitting a stack of 8 and letting them re-attract rejoins the stack with such force it smashes the magnets that make contact. So while I'm sure coming close to one of those would _hurt_, I don't think I'd either end up stuck to the magnet or having the implant dragged out of me. The implant is powerful for its size, but its size is _tiny_ (half a grain of rice is a good comparison). It's not going to be as strongly attracted as that.
  - VMG 15y ago
    What do you have in mind? I can only come up with particle accelerators, nuclear fusion reactors and special cranes on junkyards..
    - windsurfer 15y ago
- CapitalistCartr 15y ago
  I'd like to contact you regarding how you went about getting your implant. My email is in my profile.
  - AkThhhpppt 15y ago
    I'm sure it is, but apparently I can't see it, through either incompetence or measly karma. The short-form of my implant tale is here: http://discuss.biohack.me/discussion/comment/862#Comment_862 http://discuss.biohack.me/discussion/comment/862#Comment_862
  - aeontech 15y ago
    The emails in profiles are not visible to other users. This is a UI issue here that's bitten everyone.
    - CapitalistCartr 15y ago
      Well now, isn't that something I should have checked. Capitalist.Carter@gmail.com
HeyLaughingBoy 15y ago
A bit OT, but does it depend on the metal used? My wife's wrist was reconstructed using a set of metal plates after it was shattered a few years ago. However, she's had at least three MRIs (for an unrelated problem) since then. The plates may be titanium and not surgical steel, so perhaps that's the difference?
- randlet 15y ago
  That's correct. Titanium is widely used for implants and is non-ferromagnetic so you can safely be MRI'ed with a titanium implant.
  - ars 15y ago
    Isn't there inductive heating? It's conductive.
    - randlet 15y ago
      Yes, non ferromagnetic materials are still subject to some inductive heating due to eddy currents* but I have no feeling for how much. *I've had the pleasure of being MRI'd a few times in a 4 Tesla research MRI (normal MRI's operate around 1.5T) and occasionally I would get nerve stimulation due to eddy currents set up in tissue. An interesting feeling!
- jonnathanson 15y ago
  Could be. I'm in a similar situation as your wife -- wrist and partial hand reconstruction -- but I'm under strict guidance to avoid MRIs, and have to report as such at hospitals and doctors' offices. I've also got a metal fixture in one of my toes on my left foot -- but, for whatever reason, that one's never caused an issue. Pretty sure the toe plate is titanium, and the assorted hardware in my wrist and hand are not.
aplusbi 15y ago
I have a magnet implant and looked into this. I found a study about MRIs and cochlear implants and not once did the study mention any dangers. Instead their concerns were based on demagnetizing the implant, and they found that the risk of demagnetization could be mitigated by aligning the patient in a certain way. I know that cochlear implants are very different from finger magnets (cochlear implants are attached to bone) but it does challenge some of my basic assumptions. It should also be noted that it would take less than five minutes to remove the implant with a scalpel.

icegreentea 15y ago

Though it would seem that removing the magnet wouldn't be too much of a problem. I mean, it should show up under flouroscopy, and failing that, I guess you could mark the spot with tattoos with when get them implanted. Would still be a headache though.

AkThhhpppt 15y ago

There's a reason I have a Rod of Asclepius and "DO NOT MRI" tattooed on my wrist. Apparently it's quite possible to go through an MRI with implant intact, so long as the techs know about it. The inventor of these implants' advice about MRIs can be found here: http://www.stevehaworth.com/wordpress/index.php/welcome-from-steve-haworth/magnetic-faq http://www.stevehaworth.com/wordpress/index.php/welcome-from...

jonnathanson 15y ago
That is good to know. Thank you for the clarification. I'm glad the inventor took this into consideration.
jpdoctor 15y ago
> There's a reason I have a Rod of Asclepius and "DO NOT MRI" tattooed on my wrist. You realize there are other large magnets in the world besides those for MRIs?
- AkThhhpppt 15y ago
  Yes, but how many large magnetic fields does one gets stuck into while unconscious that _aren't_ MRIs? Besides, I've been exposed to serious magnets; the inverse cube law is my friend. Plus, even when I did come close to a strong magnet, all that happened was my implant flipped ends. In my finger, yes, but it wasn't painful (my implant is a cylinder, about as tall as it is wide; a disc magnet would have been much worse).
  - jpdoctor 15y ago
    > Yes, but how many large magnetic fields does one gets stuck into while unconscious that _aren't_ MRIs? If by "unconscious" you mean asleep, not many. If by "unconscious" you mean unaware, plenty. Try walking past these in a lab: http://www.youtube.com/watch?v=J2PDAnKEu9M http://www.youtube.com/watch?v=J2PDAnKEu9M FYI: Neodymium magnet strength is of order 1T, same as MRI.
    - AkThhhpppt 15y ago
      See where I mentioned the implant "rolling over"? That was caused by someone waving a stack of over 20 of these type of neodyms (http://www.magnets2buy.com/acatalog/neodymium-discs.html http://www.magnets2buy.com/acatalog/neodymium-discs.html) within an inch of my finger. Those are so powerful that splitting a stack of 8 and letting them re-attract rejoins the stack with such force it smashes the magnets that make contact. So while I'm sure coming close to one of those would _hurt_, I don't think I'd either end up stuck to the magnet or having the implant dragged out of me. The implant is powerful for its size, but its size is _tiny_ (half a grain of rice is a good comparison). It's not going to be as strongly attracted as that.
- VMG 15y ago
  What do you have in mind? I can only come up with particle accelerators, nuclear fusion reactors and special cranes on junkyards..
  - windsurfer 15y ago
CapitalistCartr 15y ago
I'd like to contact you regarding how you went about getting your implant. My email is in my profile.
- AkThhhpppt 15y ago
  I'm sure it is, but apparently I can't see it, through either incompetence or measly karma. The short-form of my implant tale is here: http://discuss.biohack.me/discussion/comment/862#Comment_862 http://discuss.biohack.me/discussion/comment/862#Comment_862
- aeontech 15y ago
  The emails in profiles are not visible to other users. This is a UI issue here that's bitten everyone.
  - CapitalistCartr 15y ago
    Well now, isn't that something I should have checked. Capitalist.Carter@gmail.com

HeyLaughingBoy 15y ago

A bit OT, but does it depend on the metal used? My wife's wrist was reconstructed using a set of metal plates after it was shattered a few years ago. However, she's had at least three MRIs (for an unrelated problem) since then. The plates may be titanium and not surgical steel, so perhaps that's the difference?

randlet 15y ago
That's correct. Titanium is widely used for implants and is non-ferromagnetic so you can safely be MRI'ed with a titanium implant.
- ars 15y ago
  Isn't there inductive heating? It's conductive.
  - randlet 15y ago
    Yes, non ferromagnetic materials are still subject to some inductive heating due to eddy currents* but I have no feeling for how much. *I've had the pleasure of being MRI'd a few times in a 4 Tesla research MRI (normal MRI's operate around 1.5T) and occasionally I would get nerve stimulation due to eddy currents set up in tissue. An interesting feeling!
jonnathanson 15y ago
Could be. I'm in a similar situation as your wife -- wrist and partial hand reconstruction -- but I'm under strict guidance to avoid MRIs, and have to report as such at hospitals and doctors' offices. I've also got a metal fixture in one of my toes on my left foot -- but, for whatever reason, that one's never caused an issue. Pretty sure the toe plate is titanium, and the assorted hardware in my wrist and hand are not.

aplusbi 15y ago

I have a magnet implant and looked into this. I found a study about MRIs and cochlear implants and not once did the study mention any dangers. Instead their concerns were based on demagnetizing the implant, and they found that the risk of demagnetization could be mitigated by aligning the patient in a certain way. I know that cochlear implants are very different from finger magnets (cochlear implants are attached to bone) but it does challenge some of my basic assumptions. It should also be noted that it would take less than five minutes to remove the implant with a scalpel.