The Therapeutic Goods Administration (TGA) of Australia has issued a safety alert concerning Gadolinium-based contrast agents for magnetic resonance imaging (MRI) scans.
The TGA has reviewed recent information relating to the potential for small amounts of gadolinium to be retained in the brain, following use of gadolinium-based contrast agents during MRI scans.
No harmful effects of gadolinium retention in the brain have been identified at this time, but the TGA is working with sponsors of these products to update their Product Information (PI) documents to reflect the new information.
Gadolinium-based contrast agents are injected into a patient's vein to enhance the quality of MRI scans of internal organs, blood vessels and tissues. MRI scans help health professionals to diagnose medical conditions. There are two types of gadolinium-based contrast agents - linear agents and macrocyclic agents.
Published studies have found that linear gadolinium-based contrast agents appear to result in greater gadolinium retention in the brain than macrocyclic agents. The TGA will continue to monitor this issue and take further action if necessary.
This issue only relates to gadolinium-based contrast agents used in MRI scans and not to other types of scanning agents used for other imaging procedures.
PI documents for gadolinium-based contrast agents have previously stated that gadolinium 'does not cross the intact blood brain barrier' and in some instances that gadolinium does not accumulate in normal brain tissue. There is now increasing evidence that this may occur.
While no harmful effects of gadolinium retention in the brain have been identified at this time, the TGA is working with sponsors to update the PI documents and is recommending judicious use of gadolinium-based contrast agents, particularly linear agents.
Health professionals are advised to limit gadolinium-based contrast agent use to circumstances where the extra information provided by the contrast agent is necessary, and in those circumstances to use the lowest effective dose and carefully consider the choice of agent. The TGA also recommends that health professionals avoid repetitive scans using these contrast agents unless deemed clinically necessary.
For details, please refer to the TGA website:
https://www.tga.gov.au/alert/gadolinium-based-contrast-agents-mri-scans
If you are in possession of the affected products, please contact your supplier for necessary actions.
Posted on 28 July 2017