What Happens If You Can’t Take Out a Piercing for a CT Scan?

Leaving a piercing in during a CT scan is not dangerous, but it can degrade the images. Metal jewelry interacts with the X-ray beam and creates bright streaks and dark shadows on the resulting pictures, potentially hiding the very anatomy your doctor needs to see. Whether that matters depends on what body part is being scanned, where the piercing sits, and what the radiologist is looking for. In many cases the scan proceeds just fine with the jewelry in place, and there are both clinical workarounds and software tools that help.

Why Metal and CT Beams Do Not Get Along

A CT scanner rotates an X-ray source around your body, collecting thousands of measurements that a computer reconstructs into cross-sectional images. When those X-rays hit dense metal, two things go wrong at once. First, the metal absorbs so many photons that the detector on the other side gets almost no signal, a problem called photon starvation. Second, the X-ray beam is polychromatic, meaning it contains photons of many different energies. Metal preferentially absorbs the lower-energy photons, shifting the beam toward higher energies as it passes through. This “beam hardening” fools the reconstruction algorithm, which expects a uniform beam, into producing errors in the final image.

The visible result is a starburst pattern of bright and dark streaks radiating outward from wherever the metal sits. These streaks can extend several centimeters beyond the jewelry itself and obscure soft-tissue detail in the surrounding area. The mismatch between the actual data and what the reconstruction algorithm expects is the core mathematical problem behind the artifact.

Does the Type of Metal Matter?

It matters a lot. Denser metals block more X-rays and produce worse artifacts. Surgical stainless steel, the material in many inexpensive body piercings, is one of the worst offenders. Titanium, a popular choice for higher-end body jewelry, produces noticeably less artifact. A study comparing spinal implants made of stainless steel, titanium, and a cobalt-chromium alloy found that titanium and the cobalt-chromium alloy both produced less artifact and better diagnostic image quality than stainless steel, with titanium performing slightly better than the cobalt-chromium in most trials.¹ Separate research using a biodegradable magnesium alloy showed it produced significantly less artifact-related noise in CT than either titanium or stainless steel.²

What does this mean for your belly ring or tongue stud? If your piercing is titanium, you are starting with a built-in advantage. If it is surgical steel or an unknown alloy, the artifacts will be worse, though still manageable in many scanning situations. Niobium and implant-grade titanium, two metals favored by reputable piercers, tend to behave similarly to titanium implants. Gold body jewelry, being extremely dense, creates substantial artifacts.

Location Is Everything

A tongue piercing will barely register on a CT of your pelvis. An ear cartilage piercing will not affect a scan of your chest. The artifact only matters when the metal sits in or very near the body region being imaged. Even within the scan field, the clinical impact depends on what the radiologist needs to see.

If you are getting a head CT to rule out a stroke, a small nose stud on the opposite side of the skull might produce a minor streak that does not obscure the brain tissue the neurologist cares about. A pair of large ear gauges, on the other hand, could throw artifacts across the temporal lobes. A navel piercing is irrelevant for a head scan but potentially problematic for an abdominal CT looking at the bowel or anterior abdominal wall. The technologist assessing your jewelry is making exactly this calculation: is this piece of metal close enough to the anatomy of interest to cause a diagnostic problem?

This is why the request to remove jewelry is not a blanket safety concern the way it is with MRI. It is an image-quality decision, and reasonable technologists weigh the specifics rather than demanding removal of every piece regardless.

CT Versus MRI Safety

Many people confuse the CT jewelry conversation with the MRI jewelry conversation, and the two are fundamentally different. MRI uses powerful magnets and radiofrequency pulses. Ferromagnetic metal in an MRI suite can be pulled by the magnet, heated by the radiofrequency energy, or both. Jewelry or devices left in place can interfere with MRI, creating artifact, distortion, or even injuring the patient.³ A CT scan, by contrast, uses X-rays. There is no magnetic field. Your piercing will not move, heat up, or cause you any physical harm inside a CT scanner. The only issue is image quality.

This distinction matters when you are weighing a technologist’s request to remove a piercing. In an MRI setting, refusal genuinely risks injury, and the scan may be canceled for safety reasons. In a CT setting, the worst case is a degraded image. The urgency of the scan and the severity of the expected artifact both factor into whether the radiologist can accept the compromise or truly needs the metal gone.

What the Technologist Can Do Without Removing the Piercing

Radiologists and technologists have several tools at their disposal when metal stays in place. The simplest is adjusting the scanner settings. Increasing the tube voltage pushes the X-ray beam toward higher energies, which are less affected by metal. Research has shown that higher tube voltages, combined with metal artifact reduction (MAR) software, significantly reduce artifact intensity compared to standard settings.⁴ The trade-off is a modest increase in radiation dose, which the radiologist may accept if the clinical question is important enough.

Beyond scanner adjustments, dedicated MAR algorithms process the raw scan data or the reconstructed image to computationally remove or reduce streaks. These work by identifying the metal in the data and either replacing the corrupted measurements with estimates or segmenting the metal out and reconstructing the image without it. Both approaches improve the detectability of structures near the metal.⁵ Most modern CT scanners in hospitals come with some version of MAR software, either built in or available as an add-on.

These algorithms are not perfect. A comprehensive review of MAR methods used for radiation therapy planning found that none was completely satisfactory, because some techniques introduce new artifacts or blur fine detail even as they suppress the original streaks.⁶ The performance also depends on the imaging dose. At certain lower dose levels, one type of MAR algorithm actually degraded images compared to no correction at all, because the noise-sensitive step of finding the metal in the raw data broke down.⁵ In practice this means the radiologist has to pick the right tool for the situation rather than blindly pressing a “fix artifacts” button.

The Catheter Spacer Technique

Sometimes removal really is necessary but the patient cannot get the jewelry out, either because the threading is stuck, the piercing is swollen, or they lack the dexterity. In these situations, medical staff can remove the jewelry and keep the piercing tract open using a simple trick documented in the clinical literature. The technique involves disinfecting the piercing site, unscrewing the bead or end piece, sliding a snug-fitting intravenous catheter (the plastic sheath, without the needle) over the exposed bar, and then pushing the bar out through the skin while leaving the catheter behind as a placeholder in the tissue tract. After the scan, the jewelry is reinserted by reversing the steps.⁷

This approach was described for navel piercings in adolescent patients, but the principle applies to many piercing sites. The key is that the plastic catheter is radiolucent, meaning it does not show up on CT, so it creates no artifact at all while keeping the hole from closing. Piercing tracts can begin shrinking within hours, especially newer ones, so a placeholder matters if you want to reinsert the jewelry afterward. If you find yourself in this situation, mentioning the catheter spacer technique to the nursing staff can be helpful, as not every technologist is familiar with it.

When the Scan Happens Anyway

Emergency departments are the most common setting where piercings simply stay in. If you arrive after a car accident and need an urgent head or body CT, nobody is going to delay the scan to wrestle with a stubborn labret stud. The radiologist reads the images knowing the artifact is there and mentally accounts for it. In many trauma situations, the diagnostic question is large-scale: is there bleeding in the brain, a collapsed lung, free fluid in the abdomen? These findings are usually visible despite nearby metal artifacts because the abnormalities and the artifacts look very different. A blood collection appears as a distinct density change across a wide area, while a metal streak is a narrow line radiating from a point source.

Where things get trickier is in non-urgent scans looking for subtle findings. A CT angiogram of the neck vessels, for example, requires crisp visualization of small arteries. A tongue piercing in that field could create enough streak artifact to obscure a critical vessel. A CT of the face to plan reconstructive surgery needs millimeter-level bone detail, and a nose ring or eyebrow barbell could compromise that. In these elective scenarios, the radiologist is more likely to insist on removal because the clinical stakes of a degraded image are higher relative to the inconvenience.

What About Dermal Anchors and Surface Piercings?

Dermal anchors, the flat-footed implants that sit under the skin with just a decorative top poking through, present a unique challenge. Unlike a ring or barbell that threads through a tunnel of tissue, a dermal anchor is held in place by tissue growing around a base plate beneath the skin surface. You cannot simply slide it out and slide it back in. Removal usually means the piercing is gone permanently, or at the very least requires a new procedure to reinsert.

For CT purposes, a dermal anchor is a very small piece of titanium (most quality anchors are titanium) sitting just below the skin. Because it is small and superficial, its artifact footprint is modest. If the anchor is on your chest and the scan is looking at your lungs or heart, the artifact is unlikely to cause a diagnostic problem because the metal sits far from the deeper structures of interest. But if the anchor sits directly over the region being evaluated, the radiologist may need to weigh whether the small artifact zone matters for the specific clinical question. In most cases it does not, and the scan proceeds.

AI Is Getting Better at Cleaning Up Metal Artifacts

The newest frontier in dealing with metal on CT is artificial intelligence. Deep learning reconstruction algorithms are being trained on datasets that include metal artifacts, learning to distinguish the streak patterns from real anatomy and suppress them during image reconstruction. Research on cone-beam CT, a type of scanner used heavily in dental and maxillofacial imaging, found that AI significantly improved both objective measurements of image quality and subjective ratings of artifact intensity and overall diagnostic quality when metallic objects were present.⁸ When combined with conventional MAR techniques and optimized tube voltage, deep learning reconstruction reduced artifact indices more than any single approach alone.⁴

These tools are rolling out across major scanner manufacturers, and within a few years the metal artifact problem is likely to shrink considerably for routine clinical imaging. That said, the underlying physics has not changed. Extremely dense or large metal objects will still starve the detector of photons in ways that no algorithm can fully recover, because the information was never captured in the first place. AI can interpolate and estimate, but it cannot invent data that the X-rays never delivered. For a small piercing, though, the combination of modern MAR software, optimized scanner settings, and AI reconstruction often makes the artifact clinically negligible.

Practical Steps If You Are Heading Into a CT Scan

If you know you have a scan coming up and your piercing is removable, the simplest path is to take it out beforehand and bring it with you in a small bag. Even if the piercing is nowhere near the scan area, removing it avoids the conversation entirely. If you cannot remove it yourself, many piercing studios will help for free or a small fee, and they can insert a glass or bioplast retainer that is invisible on CT.

Retainers made of PTFE (a flexible plastic), borosilicate glass, or bioplast are specifically designed for medical imaging situations. They keep the piercing tract open while producing no artifact whatsoever, since these materials have similar X-ray density to soft tissue. If you have piercings in areas that get scanned frequently, keeping a set of retainers on hand is worth the small investment.

If you arrive at the imaging center with jewelry you truly cannot remove, tell the technologist what the jewelry is made of. “It’s implant-grade titanium” is meaningful information that helps the radiologist decide whether to proceed, adjust settings, or apply MAR software. “I’m not sure what metal it is” is also fine to say honestly, as it helps the team plan accordingly. The worst thing you can do is hide the piercing under clothing or fail to mention it, because the technologist and radiologist need to know about any metal in the scan field before they acquire the images, not after.

Piercings and Radiation Therapy Planning

One scenario where metal artifacts cause more serious problems than routine diagnostic imaging is radiation therapy. When a CT scan is used to plan a course of radiation treatment for cancer, the image data directly feeds into dose calculations. Artifacts from metal can throw off the computed tissue densities, leading the planning software to miscalculate how much radiation is delivered to the tumor and surrounding healthy tissue. A review of MAR methods applied to radiation therapy planning found that while these algorithms improved image quality, none fully eliminated the errors introduced by metal, and some introduced additional inaccuracies like blurring or new artifacts.⁶

If you are undergoing radiation therapy and have piercings anywhere in the treatment field, your oncology team will almost certainly require removal. The margin for error in dose calculation is much tighter than in a diagnostic scan where a radiologist can mentally compensate for streaks. In this context, even small artifacts in the wrong place can have real clinical consequences, so the standard is to eliminate every avoidable source of metal in the scan region.