Traditional and cosmetic tattoo procedures have been performed for thousands of years. Unfortunately, there is much confusion regarding the overall safety aspects of permanent cosmetics. For example, based on a few reports of symptoms localized to the tattooed area during MR imaging, many radiologists have refused to perform examinations on individuals with permanent cosmetics, particularly tattooed eyeliner. This undue concern for possible adverse events prevents patients with cosmetic tattoos access to an important diagnostic imaging technique.
MRI machines are used to locate tumors and other abnormalities within the human body using extremely strong magnets. Along with these magnets, an MRI machine uses radio frequency waves to make protons in the body's cells react, emitting signals that show up as a grayscale image.
Tattoos can hinder an MRI scan depending on the ingredients used in the tattoo ink and the size of the tattoo. Since there are currently no FDA-approved tattoo inks, determining which chemicals were used in a tattoo can be tricky.
For example, the dye used in some tattoo inks contains iron, which is magnetic and very susceptible to the magnetic fields used in MRI machines. If the tattoo is in the shape of a loop, it can act as an antenna and can get increasingly hotter as the ink pigments pick up more energy from the magnets. The reaction can result in swelling of the tattooed skin and its surrounding area, as well as the flesh, feeling hot and irritated, even in the first and second-degree burns as the most serious reaction.
In consideration of the available literature and experience pertaining to MR procedures and patients with permanent cosmetics and tattoos, during the procedure you should be treated by following guidelines:
Tattoos near the eyes are particularly of concern, as the area can be very sensitive to excess heat. If you are having permanent facial tattoos (such as eyeliner, eyebrow and lip liner tattoos) to consult with your doctor and MRI technician regarding possible burn risks so that precautions can be taken.
In addition to the above, information and recommendations have been provided for patients by FDA: "The risks of avoiding an MRI when your doctor has recommended one are likely to be much greater than the risks of complications from an interaction between the MRI and tattoo or permanent makeup. Instead of avoiding an MRI, individuals who have tattoos or permanent makeup should inform the radiologist or technician of this fact in order to take appropriate precautions, avoid complications, and assure the best results."
In summary, if you are having a cosmetic tattoo you should be permitted to undergo MRI despite the rare possibility of a cutaneous reaction manifested most commonly as a low-grade burn. It is, however, important to identify tattoos that are “at risk”, such as those with pigments containing iron oxide, as well as those with a design that displays loops, large circular objects, or multiple adjacent points. These locations may be treated with a cold compress to assist with the completion of the examination. Alternatively, a towel or cloth may be placed between the cutaneous body parts in those patients who experience the typical reaction resulting from an electrical arc between 2 separate cutaneous tattoos.