MRI Contract Agents May Leave Result in Metal Gadolinium Deposits in Brain: Study
Gadolinium-based contrasting agents (GBCAs) used to improve test results from magnetic resonance imaging (MRI) may leave deposits of heavy metals in the brain, according to the findings of a new study.
European researchers warn that specific types of contrasting agents, known as “linear” GBCAs appear to leave behind gadolinium in the brain, raising potential safety questions about the widely used products for MRIs with contrast..
The study was published online last week in the journal Investigative Radiology, evaluating the results of animal testing involving two different groups of rats. One group was given injections of Omniscan, a type linear GBCA made by GE Healthcare, and another group was given a type of GBCA known as a macrocyclic agent.
The rats injected with Omniscan developed significant, persistent MRI abnormalities over time, and showed signs if signal hyperintensity even after Omniscan injections were stopped. High levels of gadolinium were found deep in the rats’ brains which corresponded to the abnormalities seen on the MRIs.
This study comes just months after researchers with the Mayo Clinic reported similar findings in the medical journal Radiology, which involved investigations into human brains after death, comparing those who had received GBCA injections to those who had not.
Gadolinium-based contrast agents are commonly given to patients before they take a MRI in order to get better results. Although the MRI contrast 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.
Sometimes referred to as gadolinium associated systemic fibrosis, NSF is a painful disorder that has no known cure and often results in confinement to a wheelchair and then death.
In 2007, the FDA limited GBCA 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 put similar restrictions on GE Healthcare’s Omniscan and Covidien’s Optimark.
The agency also required label changes for all GBCAs, warning healthcare professionals to screen patients before injecting a GBCA to identify those suffering from acute kidney injury or chronic, severe kidney disease.