Updated imaging protocol helps researchers limit gadolinium use
Implementing a new and improved imaging protocol can significantly reduce the use of gadolinium-based contrast agents (GBCAs) when treating multiple sclerosis (MS) patients, according to a new study published in the Journal of the American College of Radiology.
The authors noted that GBCAs are used regularly when imaging MS patients, often more than 60 administrations in a patient’s lifetime. Recent research has suggested there may be some serious risks associated with GBCAs, however, leading the team to wonder if they could keep such treatments to a minimum.
“Growing evidence suggests that there is deposition of free gadolinium in the brain and other organs with GBCA, even in patients with normal renal function,” wrote Jeffrey D. Rudie, MD, PhD, department of radiology at the Hospital of the University of Pennsylvania in Philadelphia, and colleagues. “In fact, the FDA recently issued a warning on all GBCA, although the clinical significance still remains unknown. Intravenous (IV) contrast also carries small risks related to physiologic and allergic reactions, as well as IV placement.”
The authors learned from prior research that enhancing MS lesions were only detected on patients who had “new disease activity” visible on noncontrast fluid-attenuated inversion recovery (FLAIR) imaging. If GBCAs are not absolutely necessary when following up with MS patients, they wondered, why automatically expose each patient to GBCAs?
“Given these findings and concerns about GBCA deposition, we sought to implement a quality improvement project to limit the use of GBCAs in MS follow-up imaging to only those with evidence of new disease activity on noncontrast FLAIR imaging,” the authors wrote. “In the implementation of this project, we sought to make the decision of whether patients had new disease activity in ‘real-time’ while the patient was still on the MRI scanner table, before making the decision to inject contrast.”
Before implementing this new protocol, the researchers held numerous multidisciplinary meetings to get the hospital’s radiology department and MS neurology division on the same page. It was agreed that a two-month trial would help them determine if the proposed change would prove effective.
During that trial, in-house computer-aided detection (CAD) software was used to perform real-time assessments of MS patients. The patients would not receive an IV before being placed in the MRI scanner, and a 3D FLAIR sequence would then be obtained. The FLAIR sequence was then assessed while additional noncontrast images were acquired, and a 3D laboratory technologist would decide if the GBCA was needed or not.
A total of 153 patients were imaged under this new protocol from Dec. 14, 2018, to Feb. 11, 2019. 3D MRI technologists using the in-house CAD system had an accuracy of 94.8%, sensitivity of 80% and specificity of 97%. This helps the team avoid using GBCAs and additional imaging exams in 87% of patients.
“This pilot protocol resulted in a drastic reduction in contrast use, whereby only 13.1% of patients received contrast, helping mitigate concerns regarding the potential negative effects of gadolinium deposition or other risks related to IV contrast,” the authors wrote. “Furthermore, this approach allowed for significant savings in terms of the costs to the health care system related to the contrast agent itself, time to administer contrast, and time for image generation and interpretation. These results are still considered preliminary given the relatively small time period, thus continued careful evaluation of the advantages and disadvantages of this protocol on patient outcomes is warranted.”
Michael has more than 18 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.