OT - Stuff that flew into MRI magnets

Of course. But, "safety" being "on" usually refers to something external and switchable. There have been revolvers with safeties, just not in the last century or so. (stipulate infinite discussion of Glock's

You guys are such geeks!

No, I doubt it was actually a revolver. I haven't seen one of those on an officer in years. That's just what the reporter wrote and I figured I was better off not to editorialize.

Sheesh!!!

Jim

Thank you.

Jim

Guilty as charged, your honor.

I've got my great-great-grandfather's service revolver (A Smith & Wesson model 2) that he carried for decades as a Milwaukee cop. There's something just really neat about owning an object like that.

Where's the fun in that, though?

Dave

That sure seems like quite a few incidents, and those were just the ones that happened to be photographed. Haven't hospital workers learned yet not to get ferrous metal objects too close to the MRI machine? You'd think there would be a policy and safety guidelines by now.

Makes me feel real confident about staying at hospitals!

Usually happens the first time they turn a new machine on. The magnets have an amazing reach and new users don't really believe the specs. Look at those pictures. Most of the junk is stuff like chairs and tables which don't get moved much. They were just too close at startup.

I think I've read that they never shut an MRI off if they can help it because it takes a lot of power to charge the magnets and several hours to stabilize the field after startup. Once it's on, it stays on until it needs maintenance or some lame brain wanders in wearing a chain mail vest.

Jim

Nope. When the magnet is ramped up (these stay up for months or years at a time), it's under the control of the field engineer or other responsible party - that's not a "user" type activity.

True.

Well, sort of. It's a superconducting magnet, so once your ramp it up, it's up until you either ramp it down, or quench it (emergency dump of cryogens - blows several thousand bucks, but gets the field down NOW).

Most of the maintenance can be done with the magnet on. Only if something goes wrong, or you need to move it to another location, would you ramp it down. They're even left ramped up driving down the road in the semi-trailer MRI scan vans.

I've got this picture in my head of a truck going down the road with motorcycles and small cars stuck all over it. ;-)

Heh... the field outside the van walls has to below a very low level, so as not to be a problem for people with magnetically sensitive implants outside of the van. Wouldn't be good press to shut down random pacemakers as you're driving down the road, y'see. Most or all of the mobile magnets are internally shielded so the fringe fields are nearly nonexistant (also gives better images, which is a nice side-effect).

Dear God...I could see the carnage as an unshielded van drove down a Florida freeway as the blue hairs took the hit as the van passed em....Cadillacs and Crown Vics suddenly swerving in all directions like wheat chaff blown from the back of a harvester.....

Gunner

I'm failing to see the problem with your plan...