Milgauss near an MRI machine?

[detyler]

Just wandering if anyone has taken a milgauss near an MRI machine. I'm an anesthesiologist so occasionally I have to go see patients in the MRI suite. I'll talk to them before the nurse anesthetist puts them to sleep, and sometimes they are already lying on the MRI table. I'm always told to take everything metal off before going into the room, and especially watches because even though the MRI is not currently running there is still a magnetic field that will magnetize automatic watches. Does anyone know if I can now leave my watch on when I go near an idle MRI machine? It's not why I bought the watch, but the nerdy engineer in me would actually like to wear my milgauss in a magnetic environment. Plus, I don't like taking off an expensive watch and walking away from it.

Thanks,

David

[Rags]

I'd give rolex a call on that one..Just to be safe.

[t e x]

How many Telsa is the machine? ...of course you'd mentioned "idle" mmmm

[LouS]

Well, a Milgauss is good for 1000 Gauss, and the MRI machine in my facility has a 1.5 tesla magnet and 1 Tesla is 10000 gauss. Of course, that's when the MRI is scanning. When idling, I don't know the strength (or extent) of the magnetic field, but I bet your radiology department or some better informed forum member who will be along in a minute has the answer.

[Robwilliams]

Originally Posted by detyler

Just wandering if anyone has taken a milgauss near an MRI machine. I'm an anesthesiologist so occasionally I have to go see patients in the MRI suite. I'll talk to them before the nurse anesthetist puts them to sleep, and sometimes they are already lying on the MRI table. I'm always told to take everything metal off before going into the room, and especially watches because even though the MRI is not currently running there is still a magnetic field that will magnetize automatic watches. Does anyone know if I can now leave my watch on when I go near an idle MRI machine? It's not why I bought the watch, but the nerdy engineer in me would actually like to wear my milgauss in a magnetic environment. Plus, I don't like taking off an expensive watch and walking away from it.

Thanks,

David

Don't mean to hi jack your thread here, but I was wondering, why would somone need to put under for an MRI? I have had a gazillion MRI's and I was awake for all of of them. None of them pleasant either I might add.

[detyler]

A lot of people have claustrophobia and just can't lie still in that tight little cave with those loud knocking noises.

Yes, I could ask the radiology department, but then I'd be calling attention to my Rolex, and I don't want to be that guy.

[detyler]

I have to admit my ignorance on this. I think that the MRI has a stronger magnetic field when it is actually scanning, but I don't KNOW this to be true. Maybe there's a radiologist on this forum that could help us out.

[hcivic91]

I guarantee I know the answer you will get from Rolex should you decide to call. "We suggest taking it off, just to be be safe."

[Paracentesis]

Your watch will be toast, don't do it.

[t e x]

Originally Posted by Paracentesis

Your watch will be toast, don't do it.

My thoughts exactly

[Tools]

I've been in the room and around a non-scanning MRI machine plenty of times and have never had an issue with a Sub, or GMT.. I find it unlikely that the Milgauss would have any issues either...

When it is operating, your watch MAY get magnetized, or it may stop or run erratically while exposed to the field if you are within the magnetic field flux influence.. But it won't destroy the watch.. just have it demagnetized if it gets magnetized...

Now, I wouldn't run the watch through an MRI machine... it may have enough pull to move some parts out of place

[Grissom]

Originally Posted by Robwilliams

Don't mean to hi jack your thread here, but I was wondering, why would somone need to put under for an MRI? I have had a gazillion MRI's and I was awake for all of of them. None of them pleasant either I might add.

Anxiety my friend......Claustrophobia....and why OPEN MRI units were developed, however due the low Tesla Field of an Open Unit, many require the better resolution of a Closed Unit, hence the Anesthesiologist.

I'm sorry you have had some unpleasant MRI experiences in the past.....as a diagnostic tool, patients often are already in an unpleasant state prior to being MRI'd.....

[Michael M.]

Originally Posted by Paracentesis

Your watch will be toast, don't do it.

I agree!!!!!!!!!

[Michael M.]

Originally Posted by Paracentesis

Your watch will be toast, don't do it.

I agree!!!!!!!!!!!

[Grissom]

And as relates to a Magnetic Field around an MRI Unit, you have both a fixed Magnetic Field and an Electromagnetic Pulse (that loud banging mentioned above). MRI creates a steady state of magnetism within the human body by placing the body in a steady magnetic field. Next, the MRI stimulates the body with radio waves to change the steady-state orientation of protons. Then, the MRI machine stops the radio waves and registers the body's electromagnetic transmission. Finally, the transmitted signal are used to construct internal images of the body by computerized axial tomography.

The Tesla strengths start at less than .2 Tesla (2,000 Gauss) then go from .2 to 0.6 Tesla (2,000 Gauss to 6,000 Gauss) then go from 1.0 to 1.5 Tesla (10,000 Gauss to 15,000 Gauss), and can then go as high as 3.0 Tesla (30,000 Gauss) and more.

My personal experience being inside near a non scanning MRI was obviously the closer i got the stronger the field (I have a pen knife that was attached to my keys, attached to my belt, that was permanently magnetized, within about 6 feet of a unit (my little experiment that day). And of course, ferromagnetic objects are a no-no and I am not sure what the ferromagnetic parts in a Rolex movement would be (As Larry has so astutely touched upon), so, aside from potentially magnetizing your watch, should a small ferromagnetic piece of the movement be jammed where it should not go, one would have more serious issue to deal with, than demagnetizing the watch.

TOAST, was, I believe, the previously noted (so succinctly by Paracentesis) "scientific" description!

Certainly an interesting question, and one I have also pondered being in Medicine as well.

[renfield33]

i am a radiologist... which is the doctor that reads the images that come out of the MRI. the magnet is always on! the magnetic field changes a little bit when it is scanning (read about gradient coils). the lowest field strength closed magnet that is really used today is 1.5T (1.5 tesla = 15 000 gauss). open magnets usually are 0.8-1T.

granted, that falls off pretty quickly once you get out of the center of the magnet. nonetheless, when i know i'm going to be near the magnet i wear a g-shock... not my GMT-II.

[detyler]

Thanks renfield33. Guess I'll take it off.

Almost did radiology, but I decided I did not have the skill set necessary to be a good radiologist. As a chemical engineer I was much better suited for anesthesiology.

David

[Dr.Brian]

Our MRI techs would not let you in the room with a metal watch, even if you wanted to take it in. Gshock or CBP, sure. But not metal. If the bracelet failed it could become a projectile and serious hazard. We recently had a tech run into the open door of the MRI scanner to help in an emergency, he forgot he had trauma shears in his breast pocket. The magnet reminded him. All was well, but, new policies are in place.

[SLS]

I had a MRI on my knee a few months back, and before I even went in to the office, I was told not to wear anything with metal on it and to remove all jewelry and leave it at home. Once at my appointment, I must have been asked 3 or 4 times if I had anything with metal on. They even asked if I had metal fillings in my mouth, so I highly doubt they would let you near a MRI with a watch on.
Scott

[LostInTime]

So at the peril of suffering the wrath of people here, I am curious what the point of the Milgauss magnetic resistance is, other than marketing. The Milgauss can handle 1000 Gauss and a previous poster stated that the lowest MRI starts at double that, doesn't seem too utilitarian to me but perhaps looks good in ads?

[Dr.Brian]

They were never designed to survive in the vicinity of high powered electromagnets. Perhaps they can survive run-ins with low powered magnets in electronics, engineering etc. Though, perhaps not.

[Joey_V]

Originally Posted by Robwilliams

Don't mean to hi jack your thread here, but I was wondering, why would somone need to put under for an MRI? I have had a gazillion MRI's and I was awake for all of of them. None of them pleasant either I might add.

Simple, because when you had an MRI it was non-emergent and likely you were stable. But if you were altered and you were fighting the machine - you would not stay still for the MRI, especially if you had some pathology going on.

Keep in mind that the MRI takes a good 20-40 minutes and if you're not cooperative for that amount of time, you will ruin the scan.

A CT scan takes only 1-10 minutes, much more manageable for the unruly patient. A quick sedative is ok.

[Grissom]

Originally Posted by LostInTime

So at the peril of suffering the wrath of people here, I am curious what the point of the Milgauss magnetic resistance is, other than marketing. The Milgauss can handle 1000 Gauss and a previous poster stated that the lowest MRI starts at double that, doesn't seem too utilitarian to me but perhaps looks good in ads?

The original Milgauss was introduced in 1956, I believe, for those who worked in Power Plants and Medical and Research Facilities where electromagnetic fields might be present. The original Milgauss thus significantly predates MRI units, and the higher tesla generating equipment of today.

The current Milgauss (a reissue of the original) would be, in my opinion, somewhat "marketing" oriented....but again, in 1956, the rating was plenty good enough for 1956 technology, I would imagine. Perhaps others can add to the thread.

[newdude]

Being a MRI Tech, I am considering buying a milgauss. I will try it in my 1.5T shortbore magnet. I highly doubt that it will stay magnetized. Just put it through a Weller 75 watt soldering gun and this will demagnetize anything ferromagnetic with a few passes(if you can get it through). I think the 2010 and up Millies should have the blue parachrom spring which is non ferrous. If I have problems within the first year, I'll just send it to an A.D.

[Andad]

[jerseyden]

I had a MRI scan on Monday and was told to remove my watch.

[Celter]

Of course your watch would be toast wearing it in the MRI machine. And you will not be permitted to find out, as it could possible harm, not only your watch, but the much more expencive MRI unit and possibly even the patient. The more important question is: how far away can you be wearing your watch? As a radiologist I daily wear my watches, no Milgauss, in the control room outside the MR room. I have never noticed any magnetization from this.
And by the way the MRI machine is always "running", as the magnetic feld is always on. The 1,5 T field strenght is in the center of the magnet and the magnetic field diminishes very quickly with increased distance to the magnet.

[renfield33]

wow.. is this a thread resurrection?

[masterserg]

Interesting thread. I'd get an Oakley vault and drop the watch in one of the lockers they have outside the MRI room. Why risk it?

As per the anesthesia .... I had a shoulder MRI a while ago and I am nowhere near claustrophobic ... After the first 20 minutes looking at the straight line I started to get uncomfortable and a tad anxious ...

[ecsub44]

I'd be less concerned about the the watch becoming magnetized and more concerned with your hand being cut/scraped as it violently rips the watch from your arm.

Search YouTube for videos on how strong the magnetic field is in/around the machine.

Old thread. Nice.