MRI Contrast Agent Risks Will Be Focus of Radiology Expert Meeting

A conference of radiologists set to meet over the next week will focus heavily on the safety of contrast agents used in magnetic resonance imaging (MRI) examinations, some of which have been linked to severe side effects. 

The American Roentgen Ray Society (ARRS) holds its 2017 annual meeting in New Orleans from April 30 to May 5, and officials indicate that concerns about contrast agents, particularly gadolinium-based products, will take center stage, according to a report by Medscape.

A number of sessions are planned to address long-term side effects, accumulation in the brain, and effects on kidney function.

Gadolinium based MRI contrast agents are used to enhance the images and allow physicians interpreting the exam to distinguish blood vessels from nearby tissue. According to the American College of Radiology (ACR), gadolinium-based contrast agents are used on about 30 million patients annually.

Although the MRI dyes are generally believed to be safe, several years ago concerns emerged about a link between MRI gadolinium contrast agents and a severe and life-threatening skin condition, known as nephrogenic systemic fibrosis (NSF), which was found to occur among patients with impaired kidney function, causing their skin to thicken and harden, severely restricting movement and often resulting in wheelchair confinement and then death.

In 2007, the FDA limited gadolinium contrast doses in most patients and contraindicated it for others, which limited the risk of NSF. In September 2010, the FDA went even further and banned the use of Bayer’s Magnevist on patients with kidney problems, due to the heightened risk of NSF.

The agency also required label changes for all gadolinium agents, warning healthcare professionals to screen patients before injecting gadolinium to identify those suffering from acute kidney injury or chronic, severe kidney disease.

New safety concerns have come up in the last several years, regarding the buildup of gadolinium in the brain.

In March 2015, a study published in the medical journal Radiology examined the brains of cadavers and found that those who had received gadolinium injections had deposits in the brain, while those who had not received such injections did not.

In June 2015, a study by European researchers in the journal Investigative Radiology found similar deposits in the brains of rats injected with Omniscan, a GBCA (gadolinium-based contrast agent) made by GE Healthcare. The rats developed significant, persistent MRI abnormalities over time, and high levels of gadolinium were found deep in the rats’ brains.

The FDA says that it is using its National Center for Toxicological Research to study the potential safety risks, announcing gadolinium contrast agent safety signals were under review in July 2015.

The ACR notes that studies have found gadolinium deposits can build up in bones and other organs as well.

Last year the ACR released new guidelines on the use of gadolinium-based contrast agents, urging doctors to consider a number of factors when deciding whether gadolinium MRI contrast agents should be used. The new Manual on Contrast Media includes revisions to guidelines on acute kidney injury and contrast-induced nephropathy, use of contrast media on children, adverse reactions, use on pregnant patients and other areas.