From the October 2017 issue of HealthCare Business News magazine


Guerbet, one of the major gadolinium companies, published a statement shortly after the PRAC findings, saying it did not “intend to request a reexamination of the recommendations.”

In April, the American College of Radiology chimed in on the discussion, stating that “although gadolinium accumulation appears to be dose-dependent, there remains no evidence of cellular toxicity, nor is there credible evidence of neurologic sequelae after over 300 million worldwide human doses.”


From that perspective, removing valuable diagnostic contrast agents from the market would be inappropriate without any proof that they were harming patients. The ACR called for more research into the clinical consequences of linear gadolinium accumulation, emphasizing that the contrast agents have “significant and well-documented diagnostic utility,” and in some instances may have benefits over their macrocyclic counterparts.

The ACR also advised that measurement by mass spectrometry has revealed that gadolinium deposition rates for linear and macrocyclic agents vary within a given class and that different chemical forms of gadolinium appear to be depositing within tissues, some of which would be undetectable using MR.

This, it concluded, suggested that while MR signal changes led to the discovery of gadolinium accumulation in the brain, they are less reliable for determining the quantity of gadolinium deposition in general.

Chipping away at the mystery
Unraveling the mystery of gadolinium accumulation is a scientific process and it starts with testing various hypotheses.

One question researchers have had about the risks of gadolinium accumulation concerns which patients are most susceptible to having the contrast agent accumulate in their system. One possibility could be that a compromised blood-brain barrier is more likely to experience accumulation of the agent, but research published in Radiology in June suggests otherwise.

Dr. Robert J. McDonald of the Mayo Clinic and his team examined postmortem neuronal tissue samples from five patients with normal brain pathology who had multiple gadolinium-enhanced MR exams between 2005 and 2015, and 10 patients who underwent MR exams without the contrast agent.

“Our results suggest current thinking with regard to the permeability of the blood-brain barrier is greatly oversimplified, as gadolinium appears to accumulate even among patients with normal brain tissue and no history of intracranial pathology,” McDonald said at the time.

October 2017 Magazine

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