Piercings and the MRI

Katy Peters needed to get an MRI for a radical hysterectomy surgery she had coming up. Her doctor told her that should would need to remove her nipple jewelry beforehand for safety (She had a barbell in each nipple). After talking with her piercer, she decided to sign the waivers and go ahead with the MRI while her jewelry was still in.

MRI stands for Magnetic Resonance Imaging, and the MRI unit is a giant super-powered magnet, you might imagine that her jewelry came out like Magneto showed up and went to town on her nipples.

Except Katy’s barbells stayed put and everything was fine.

The most common fear someone has when approaching the MRI with piercings is having the piercings magnetically removed in a painful way, but a far lesser known and much more common issue is called thermal heating. Like tin foil in a microwave, metal can resonate with the waves in the MRI and get hot. Like painfully so. According to this 2012 study, thermal heating is responsible for 70% of MRI injuries.

So when your doctor is a little iffy about you leaving your jewelry in, it’s because of the potential for injury involved.

Or as one MRI technician told me during a (cough) heated discussion we had: “How am I supposed to know what your jewelry is made of? How do you know what it’s made of? Did you make it?”

How Come Katy's Jewelry Didn't Come Out?

First, Let’s talk about why Katy’s nipple barbells stayed put.

She went and talked to her piercer about the MRI and was given this advice:

“The barbells were surgical-grade,” she says, “and would not need to be removed. They were made of the same material that bone pins, artificial joints, and surgical screws are made from (which obviously cannot be removed before an MRI) so the removal notice from the hospital was precautionary, given that many folks are unaware what type of metal they have in their body.”

The APP, in their FAQ on jewelry in the MRI concur.

316L stainless steel

This version of stainless is actually used in some heart surgeries for stents. It’s been shown to be safe in the MRI during lab tests. However, this kind of stainless is most likely to cause artifacts in the MRI readings, making your results harder to read if the jewelry is right near what the doctors are trying to look at.

316LVM implant grade stainless (ASTM-138 compliant steel)

This kind of stainless is used in bone pins and other implants. Studies done on this material using surgical staples made of the same steel produced neither heat, nor movement when put in the MRI. In other words, you’re good to go.

What’s the difference between 316L and 316LVM, you ask? As far as the MRI is concerned, they’re likely the same, i.e. fine, but in case you were wondering: The L stands for Low, as in Low Carbon content, which reduces tarnishing from contact with stuff like, well, you. The VM stands for Vacuum Molded, which means it was molded in a special vacuum chamber which seriously reduces contaminants. That’s why 316LVM is the gold standard for steel implants.

But the takeaway is that neither of these steel grades should cause any issue with the MRI except for artifacts.

Grade 5 titanium

This grade of titanium is commonly used in dental implants and those implants are deemed safe for the MRI. For added piece of mind, there’s never been an issue with any kind of titanium and the MRI that I could find. Ever. Titanium isn’t ferromagnetic, and so shouldn’t cause any issues at all except for a tiny amount of artifacts on the MRI results. It’s way better than stainless, but there’s still some interference, so if your piercings are right on top of whatever the doc is trying to see (And we’re talking millimeters) then you might have a problem.

Implant grade titanium  (ASTM F-136 compliant titanium)

This stuff is made out of material that’s been tested and retested in MRIs. You are golden.

How does Niobium fare in the MRI?

While titanium and surgical stainless steel have had rigorous testing and some anecdotal support for their safety in the MRI, niobium does not have much info on how it performs during medical testing. In studies done on Cochlear implants containing niobium rings, the rings were found to exhibit heating of less than .1 degree Celsius, or about .18 degrees Fahrenheit, so not a notable amount of heating. The rings also exhibited zero movement in the MRI.

Interestingly, niobium is used in some implants, most notably some newly designed stents that are between 75-97% niobium. Why did they choose to work with niobium? Because it reduces artifacts in the MRI and because it’s very non-allergenic.  Having said that, I wasn't able to find a source who could say that niobium jewelry is safe to wear in the MRI. So the jury is still out on that last one.

Glass

Shouldn’t cause an issue with your scan as long as it has no additives. So if your glass has sparkly things inside, you might want to take it out, just in case.

Stone

Stone is a bit iffier, because remember that stone is not necessarily pure. It can contain iron, silver, and all kinds of trace metals running in veins through the rock. In my previous blog post on the MRI, I mentioned that patients received severe burns from silver filaments in their clothing (This is why you wear a hospital gown into the MRI today). So tiny bits of metals in your stone jewelry could theoretically heat up.

Katy Peters, when she had her MRI done,

kept her nipple bars in just fine and experienced no troubles because they were implant grade material.

But research done using lower grades of steel has found that comparable sized materials (Like steel shrapnel or shotgun pellets made of steel rather than lead) showed very little heating, but enough movement at high power levels to cause discomfort.

In other words, no matter what you’re wearing you probably won’t have to worry about the Magneto effect. But thermal heating might still cause an issue.

As a last bit of encouragement, almost all MRI labs have ferromagnetic metal detector wands that they use to scan people. Lots of people have gotten a little metal under their skin from welding or industrial work, so it’s pretty common to have to scan people if there’s a risk.

Ask them to give your jewelry a go with the wand. If the wand doesn’t beep, you’re probably good to go.

And a final note from the MRI technician that I argued with about this subject:

“Don’t they make plastic retainers you can put in your piercings?”  Yes, they do.

The other issue that can come up is what are called artifacts. Artifacts are when something makes the MRI results harder to read. Metals of any kind can make the magnetic field scatter a bit around them and this results in a weird spot. Doctors can’t see around this spot very well because of the interference.

The appearance of “snow storm” artifacts are actually used to diagnose a burst implant or migration of silicone injection fluid. On an MRI, they look like fuzzy white dots or lines, and they’re hard to see through. So if what you’re looking for is right behind it, forget it.

Silicone jewelry & artifacts

Aside: Never get raw silicone injected into your body. It can cause abscesses, infections, and terrible things. There, I said it.

The problem is called “chemical shift”. If you think of an MRI as a microscope getting focused, the big things to get clear are water and fat. When you get these two into focus, everything else is easier to see. When silicone is present, it can cause a kind focus error, where the water and fat are harder to see clearly.

When MRI folks are working around something like a breast implant, they use special techniques to try and clarify the image. They basically say, “All this stuff is silicone, not fat or water, don’t be confused.” And the MRI focuses accordingly. Without this correction, some lines on your MRI might appear thicker than they should.

In other words, if you’re wearing silicone you might want to think about removing it for the MRI.

The MRI Follow-up About Silicone

After posting my original blog, we got a lot of feedback from Facebook (Shoutout to Facebook users Liz, Larissa, and Megan for their great questions). I decided that a follow-up would be good, since there’s not a lot of information out there on some of these questions.

In a surprising turn, Liz mentioned having images in an MRI spoiled by her silicone eyelets. Silicone, being non-metallic, is totally safe to wear in an MRI, but it can cause significant artifacts. Other users have reported that similar things happen during CT scans and X-rays. How close your jewelry is to the area they are trying to scan is obviously a factor.

I double confirmed this with medical professionals and a review of studies done on silicone in the MRI. Given its use in medical procedures, reducing silicone artifacts is a big deal. It’s particularly a problem with burst breast implants, where an MRI would be ideal for showing the extent of the damage, but the artifacts that the silicone causes in the imagery are an issue.

Since MRIs are expensive, you don’t want to have something in place that will skew results and force you to have a second one done.

Organic jewelry & artifacts

You might think that information would be limited for wood, stone and glass, but it actually isn’t. Thanks to the magic of foreign bodies, aka splinters and such, the effects that these materials have on MRIs is readily known.

Glass is radiopaque, meaning it shows up really solidly on radiographic scans like X-rays and CT scans (Which are really an X-ray variant).

So if you’re wearing glass and going in for this kind of thing, there’ll be a big white spot where the glass is. Great if you have a glass splinter, bad if your doctor is looking for something behind your plugs. But that’s only a problem for something super localized, like right behind whatever glass you’re wearing.

This study and several others that I found tested the ability of different technicians to find foreign bodies imbedded in a sheep’s skull, and include materials like glass, stone, plastic and wood.

In all of the studies I found, I wasn’t able to identify any artifacts caused by these materials. In fact, for finding foreign bodies, the CT scan was actually king. Wood, glass and plastic were all nearly invisible to the MRI, while stone could be seen for reasonably large pieces (Greater than 2mm). I also confirmed with a doctor that none of these materials will create notable artifacts on an MRI.