Anyone who’s had an MRI (Magnetic Resonance Imaging) pretty much knows the drill on removing jewelry, hair clips, belt buckles—anything metal that can interfere with the scanning process. But there are two other precautions you need to take to avoid some potentially serious MRI health risks.
Gadolinium is a paramagnetic metal ion that is approved by the FDA to provide contrast during an MRI. While a contrast agent is not always required for an MRI, many times its use is requested to provide additional diagnostic information that cannot be obtained by an MRI without contrast. Gadolinium contrast is not without risks though. According to the FDA,
…certain patients who receive GBCAs appear to be at an increased risk for developing a serious systemic fibrosing disease, NSF. The patients at risk are those with acute or chronic severe renal (kidney) insufficiency (glomerular filtration rate < 30 mL/min/1.73m2); or renal dysfunction due to the hepato-renal syndrome or in the perioperative liver transplantation period. In the hepato-renal syndrome or in the perioperative liver transplantation period, the risk applies to any severity of renal dysfunction.
There is no known treatment for NSF, and NSF has been associated with each of the five FDA-approved gadolinium contrast agents: Magnevist, MultiHance, Omniscan, OptiMARK, and ProHance.
If you’re scheduled for an MRI, ask your doctor whether it is absolutely necessary to have gadolinium contrast and make sure you fully discuss the benefits and risks for your specific situation.
The FDA issued a warning (3/5/09) that wearing certain medicated adhesive patches during an MRI scan could lead to skin burns. Some transdermal patches contain aluminum or other metals in their non-adhesive backings, and the metal is not plainly visible—nor is it in direct contact with the skin. But the metal can conduct electricity that can cause burns.
Not all patch manufacturers include a safety warning on their labels regarding the potential danger during MRI scan. In fact, it was Teva Pharmaceutical’s fentanyl transdermal system that brought the issue to light at the FDA in January. The FDA investigated and found that a similar warning was also missing on a variety of transdermal patches delivering medications—both prescription and OTC.
If you are using a medicated transdermal patch, the FDA recommends you alert your MRI facility to this fact and that you also bring it to the attention of your nurse and/or technician on the day of the exam.