Studies have shown that gadolinium-based contrast agents (GBCAs) can leave traces of gadolinium in the brain. By and large, the diagnosis tool is considered safe for non-renal insufficient patients. However, research over the last few years has made medical policy advocates think differently about the way we should use GBCAs.
In a 2013 study conducted by the Hyogo Cancer Center in Japan, abnormal T1 shortening was found in patients who had been administered GBCAs multiple times, in particular, gadopentetate dimeglumine and gadodiamide. These findings were bolstered by a study from the University of Heidelberg, which also found abnormal T1 shortening as a response to gadolinium retention. They also learned that when the gadolinium is latched to the chelating agent in a macrocyclic molecular structure, the MRI signal intensity did not experience the same increase as patients who had undergone scans with GBCA linear molecular structure. A subsequent Mayo Clinic study found gadolinium deposits in postmortem tissue in small population of patients.
These studies provoked the European Medicines Agency (EMA) to recommend facilities stop the use of four GBCAs: Gadobenic Acid (MultiHance), Gadoversetamide (Optimark), Gadodiamide (Omniscan), Gadopentetic Acid (Magnevist).
U.S. officials had a reverse reaction. The Food and Drug Administration (FDA) announced last month that they have “not identified adverse health effects from gadolinium retained in the brain after the use of gadolinium-based contrast agents for magnetic resonance imaging”. However, they pledged to continue “to asses the safety of GBCAs” by carrying out a study on GBCA retention in rats.