A new study suggests that gadolinium retention experienced by some patients following the administration of a gadolinium-based MRI contrast dye may not be dose dependent.
Instead, retention may be the result of gadolinium interacting with other variables, such as brain tumors and brain irradiation treatments.
The research, which was published last month in Radiology, analyzed the records of 145 pediatric patients who had received intravenous injections of gadolinium-based MRI contrast dyes.
The subjects were divided into two groups: primary brain tumors (structural changes) and patients with neuroblastoma without disease in the brain (no structural changes). The primary brain tumor group was further divided into the following treatment groups: radiation, with or without chemotherapy; chemotherapy alone; and no therapy.
An analysis of the data indicated that changes presumed to be entirely secondary to gadolinium deposition in the brain were much more significant in patients who had primary brain tumors treated with radiation, independent of the dose of gadolinium they received.
The study authors suggested that more research is needed to determine if brain tumor treatment with radiation results in more gadolinium deposition, regardless of the dose administered.
“There are a lot of unknowns regarding gadolinium deposition in the brain,” Benita Tamrazi, MD, a neuroradiologist at Children’s Hospital Los Angeles and first author on the study said in a statement announcing the findings.
“Understanding that the process is not dose dependent and that other factors are at play, such as structural changes of the brain with tumors and radiation, will hopefully help us learn more about the underlying mechanism of deposition and ultimately identify any possible clinical implications of deposition.”
Gadolinium is heavy metal that does not occur naturally in the human body. It is used in MRI contrast dyes because its magnetic properties help images show up better on a scan.
There are currently 8 gadolinium-based MRI contrast dyes approved for sale in the United States:
Until recently, the only known side effect associated with gadolinium-based MRI contrast dyes was a condition called nephrogenic systemic fibrosis, or NSF, which only occurs in people with pre-existing kidney failure.
However, several recent studies have suggested that gadolinium may be retained by the brain and other parts of the body long after an MRI, even among those with normal kidney function.
In December 2017, the U.S. Food & Drug Administration (FDA) announced a new class warning regarding the potential for gadolinium retention. Among other things, the agency ordered the manufacturers of gadolinium-based contrast dyes to add information regarding this risk to their product labels.
A growing number of MRI contrast dye lawsuits claim that gadolinium retention can result in serious and debilitating adverse symptoms – Gadolinium Deposition Disease – and claim that the manufacturers of gadolinium-based contrast agents failed to warn the public of this danger.