Contrast agents are widely used for magnetic resonance imaging (MRI) and angiography., These agents are administered intravenously and enhance the detail and clarity of images for more precise diagnoses., Although generally considered to be safe, the use of contrast agents may result in mild to severe adverse effects.
Gadolinium-based contrast agents (GBCAs) have been approved for clinical use for over 20 years and remain a standard contrast-enhanced MRI technique that further improves the detection and visualization of morphologic features.– There are two structurally different categories of GBCAs available; linear contrast agents and macrocylic contrast agents, which are considered to be the most stable since they have lower dissociation constants., In recent years, GBCAs have been highlighted due concerns associated with potential adverse events. Recent studies have found that GBCAs may have nephrotoxic potential, raising questions about the renal safety of these agents.,, In addition, questions about the retention of gadolinium in the body, particularly in the brain after MRI, prompted evaluations from various regulatory organizations. For instance, the Food and Drug Administration (FDA) reviewed GBCAs and found that while gadolinium retention has not been directly linked to adverse effects in patients with normal renal function, a new class warning was required. A similar review by the European Medicines Agency (EMA) resulted in recommendations to restrict the use of some linear GBCAs and the suspended authorization of others. Similarly, Health Canada states that the use of macrocylic agents may be preferable in certain patients, especially those for whom repeated doses of GBCAs may be required, as well as vulnerable patients including pregnant women and children.
The current Rapid Response report will seek to identify and synthesize the evidence around the risks and safety of macrocyclic and linear GBCAs for adults undergoing MRI.
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