Nano-coating To Make Implants MRI Safe

Makarand writes "Patients who have implants containing any kind of metal cannot be MRI scanned as the powerful electromagnetic radio waves can induce currents large enough to heat the metal in implants to over 70 C and damage surrounding tissue. Now, Biophan, a biomedical devices company, has developed a nano-coating material that can protect implants by preventing most of the radio waves from reaching the internal components of the implant by reflecting them. It's high electrical resistance also prevents currents from flowing around the implant's surface and heating any nearby body tissue. Biophan's coating is a mixture of poorly conducting nanoparticles held in an insulating matrix. The coating is a mere three micrometres thick and can cut the energy induced in an implant by 89 per cent."

Comments

Wow

[Gangis]

I had a cochlear implant put in 4 years ago and I kind of wish we had that technology for it then... It kind of sucks not being able to use some diagnostic tools. When I first got my implant, I was given a card that specifically excludes me from getting a MRI with a strength of one tesla or more and that if I needed one, I would have to have the magnetic portion taken out surgically.

pulled out

[SuperBanana]

Patients who have implants containing any kind of metal cannot be MRI scanned as the powerful electromagnetic radio waves can induce currents large enough to heat the metal in implants to over 70 C and damage surrounding tissue.

That's not the only problem- there's the whole magnetic force issue. Remember the last Bond movie, where he's in the MRI room? It's not an exaggeration- anything ferrous within a 20+ foot radius will, in fact, get picked up and pulled toward the center of the machine. That's why, unlike the Bond movies, nothing ferrous is ever supposed to be allowed into the same room.

A child at Westchester Medical Center was killed a year or two back when an oxygen cylinder against a wall was launched into the center of the MRI machine(it literally flew through the air into the center), crushing his skull.

Another "famous" incident involved a prison inmate who was not killed or injured, but the policeman guarding him lost his gun- I can't remember if it was holstered or in his hands, but it ended up hitting the MRI machine, AND discharging- not to mention I think it also partially damaged the dewar vessel surrounding the magnet. In both cases, the nurses and doctors hadn't managed to think through the most basic safety issue- NOTHING metal goes in an MRI room, PERIOD(Westchester never did publicly "figure out" how the oxygen cylinder, which never should have been in there in the first place, got there- much less why the nurses didn't remove it.)

Now, imagine if the metal object was inside your knee...forget "damaged tissue", you could end up with a face-knee transplant.

hmm...

[EMH_Mark3]

Could you coat, say, a gun with that stuff and make it invisible to metal detectors?

Other shielding possibilities?

[boredman]

Could this technology also be used to shield RF-sensitive circuits, or perhaps EMP-harden ICs?

-boredman

Re:Metal implants?

[Muhammar]

I heard of a story about a worker who got into an MRS head scan. He started screaming and they pulled him out but it was too late - a steel splinter that was embeded in one of his eyes from a work-related injury and got undetected for years started moving around in the >15 Gauss magnetic field.

[Scrambled eyes, anyone?]

RE: Eye Shrapnel

[some guy I know]

... a steel splinter that was embeded in one of his eyes ...

That's why you should get a head X-Ray before you get an MRI (at least your first one).
When I got an MRI, the doctor recommended that I get an X-Ray because I occasionally use a grinder to sharpen my lawnmower blade, but it's always a good idea to get one no matter what, at least for your first MRI.
It's inexpensive insurance against a possible cause of blindness.

High School Field Trip

[jasno]

I remeber going on a high school field trip to the University of Washington to check out their MRI equipment. It was part of my occupational electronics course, and our Prof. was an ex-GE medical guy with connections(excellent Professor, too). I had prepared a coil of 10ga copper wire(maybe 8" across, 3/4" thick bundle of wire, don't remember how many windings) with a flashlight bulb attached. I also brought an audio cassette tape and an aluminum vent filter(12"x24"x1/4" or so).

I tried moving the coil of wire in the opening of the MRI and didn't see anything on the bulb, so I removed it and shorted the wires together. When I placed the loop near the opening and attempted to twist it, it resisted with something like 10 ft/lbs of torqe. It was incredibly eerie having something floating in midair resist so strongly. The audio tape was almost ripped out of my hand and had the bias stripped off so it was no longer usable. When we stood the aluminum filter on its end on the patient bed and let it fall, it fell like it was submerged in a viscous liquid.

They told us that a monkey wrench takes 3 guys to pull it out and if you walk into the room with steel toed boots you can feel your legs getting pulled to the side. Very cool stuff.