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Author Topic: MRI Scans, Can They Damage Nerves?  (Read 3794 times)

Offline Titanscape

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MRI Scans, Can They Damage Nerves?
« on: 24/04/2009 16:45:09 »
Can MRI scans damage the nervous system at all, or have any lasting effect?

Are they good for accuracy in this way? Clear, sharp pictures?


 

Offline graham.d

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MRI Scans, Can They Damage Nerves?
« Reply #1 on: 24/04/2009 17:28:36 »
I don't believe that there would be any damage from an MRI scan. It is a big and complex piece of kit but does not use any nasty radiation (like X-rays) that could harm human tissue. It relies on a VERY strong magnetic field though, so you should be asked if you have any magnetic material in your body (like iron shrapnel for example). Otherwise it can tear this sort of thing out of you in a rather unpleasant and direct way. There is a pulsed RF field used too, but this is probably no worse than using a mobile phone.

They produce very good images and have the benefit of resolving the differences between soft tissue, so can image organs well, including the brain.
 

Offline RD

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MRI Scans, Can They Damage Nerves?
« Reply #2 on: 24/04/2009 19:09:34 »
The very strong magnetic field in an MRI is constant.
If strong magnetic fields are pulsed they can induce electrical currents in nerves and thus stimulate them...
http://en.wikipedia.org/wiki/Transcranial_magnetic_stimulation
« Last Edit: 24/04/2009 19:12:20 by RD »
 

Offline graham.d

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MRI Scans, Can They Damage Nerves?
« Reply #3 on: 24/04/2009 21:25:28 »
RD, the strong magnetic field is indeed constant but there is also a pulsed RF field (if you like a pulsed radio wave) that causes the resonance and it is the relaxation of this resonance that is subsequently detected and which then forms the image. This would do no more harm than using a cell phone.
 

Offline RD

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MRI Scans, Can They Damage Nerves?
« Reply #4 on: 28/04/2009 05:11:39 »
the strong magnetic field is indeed constant

Yep the electromagnet is even on when the cleaners are in ...

 

  

http://mrimetaldetector.com/blog/?p=19
« Last Edit: 28/04/2009 05:13:12 by RD »
 

Offline Titanscape

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MRI Scans, Can They Damage Nerves?
« Reply #5 on: 12/05/2009 12:24:18 »
Thanks, another question is, would fillings in  my teeth mean I cannot have an MRI scan of my head?
 

Offline techmind

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MRI Scans, Can They Damage Nerves?
« Reply #6 on: 12/05/2009 18:26:44 »
Fillings are made of mercury amalgam and are not magnetic so no big problem there.

I think the RF fields are 10's MHz rather than microwaves so probably no issues there either.
 

Offline RD

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MRI Scans, Can They Damage Nerves?
« Reply #7 on: 13/05/2009 04:32:16 »
would fillings in  my teeth mean I cannot have an MRI scan of my head?

Some metal implants a problem, e.g. pacemakers or shrapnel.
« Last Edit: 13/05/2009 04:39:08 by RD »
 

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MRI Scans, Can They Damage Nerves?
« Reply #7 on: 13/05/2009 04:32:16 »

 

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