In a recent article in the journal Radiology, a team of researchers in the Department of Radiology at Massachusetts General Hospital reported on their development of a potential alternative to gadolinium-based contrast agents (GBCAs) for magnetic resonance imaging (MRI). GBCAs help produce high-quality MRI images but carry health risks in a small number of patients.

Chief of Pediatric Imaging Michael S. Gee, MD, PhD and MRI Clinical Director Pamela Schaefer, MD answer questions about the use of GBCAs for MRI and what patients need to know.

What is gadolinium and how does it work in imaging?
Gadolinium is a naturally occurring element that forms the basis of all currently approved contrast agents for MRI. Contrast agents are dyes that are injected into a patient’s veins by IV to help makes images clearer and improve diagnostic accuracy for some types of MRI exams. Gadolinium is typically removed from the body by the kidneys within 24 hours.

What are the pros and cons of using GBCAs?
GBCAs can increase the speed and accuracy of an MRI for children and adults. Some diseases such as cancer and many infections are best seen using GBCAs. However, the benefits must be carefully weighed against the risks.

For most patients, reactions to GBCAs are extremely rare and not life-threatening. In patients with severe kidney disease, GBCAs can cause a potentially fatal thickening of soft tissue called nephrogenic systemic fibrosis (NSF). New evidence also suggests that a specific type of GBCA can accumulate in very small amounts in the central nervous systems of patients who have several MRIs, but the risks are unknown.

When do you use GBCAs?
We only use GBCAs when they are necessary to assist a diagnosis. We do not use GBCAs in patients who are pregnant, at risk of an allergic reaction or have kidney disease.

How does Mass General use contrast safely in MRI?
At Mass General, we screen for kidney problems before using a GBCA. We decide if it adds diagnostic value, and we weigh the immediate benefits against the potential for long-term risks on a case-by-case basis. If we decide that we need a GBCA, our protocol is to use the safest agents with the lowest risk of gadolinium accumulation in the body.

We are also developing new MRI techniques that enable us to produce high-quality diagnostic images without contrast.