Contrast-enhanced magnetic resonance imaging (MRI) is a commonly used diagnostic tool. Compared to the standard gadolinium-based contrast agents, ferumoxytol (Feraheme, AMAG Pharmaceuticals, Waltham, MA), used as an alternative contrast medium, is feasible in patients with impaired renal function. Other attractive imaging features of intravenous (IV) ferumoxytol include a prolonged blood pool phase and delayed intracellular uptake. With its unique pharmacological, metabolic and imaging properties, ferumoxytol may play a crucial role in future MR imaging of the central nervous system (CNS), various organs outside the CNS, and the cardiovascular system. Preclinical and clinical studies have demonstrated the overall safety and effectiveness of this novel contrast agent with rarely occurring anaphylactoid reactions. The purpose of this review is to describe the general and organ specific properties of ferumoxytol, as well as the advantages and potential pitfalls associated with its use in MRI. In order to more fully demonstrate the applications of ferumoxytol throughout the body, an imaging atlas was created and is available as supplementary material online.

Background and Purpose Despite the label change and FDA’s boxed warning added to the Feraheme® (ferumoxytol, AMAG Pharmaceuticals, Waltham, MA) label in March 2015, radiologists have shown increasing interest in using ferumoxytol as an MRI contrast agent as a supplement or alternative to gadolinium. The goals of this study are to provide information regarding ferumoxytol safety as an imaging agent in a single center, and to assess how Feraheme® label change may affect this potential, currently off label indication. Materials and Methods This retrospective study evaluated the overall frequency of ferumoxytol related adverse events (AEs) when used for CNS MRI. Subjects with various CNS pathologies were enrolled in Institutional Review Board approved imaging studies. Ferumoxytol was administered as multiple rapid bolus injections. The risk of AEs was correlated with demographic data/medical history. Results Safety of 671 ferumoxytol enhanced MR studies in 331 subjects was analyzed. No anaphylaxis, life-threating or fatal (grade 4 or 5) AE was recorded. The overall proportion of ferumoxytol related grade 1–3 AE was 10.6% (8.6% occurring within 48h), including hypertension (2.38%), nausea (1.64%), diarrhea (1.04%) and headache (1.04%). History of one or two allergies was associated with increased risk of AE (14.61% vs. no allergies of 7.51%, p=0.0069). Conclusion The frequency of mild ferumoxytol related AE was comparable with literature results, and no serious AE was recorded. While the recommendations in the boxed warning should be followed, serious AE appear to be rare events and with proper precautions ferumoxytol may be a valuable MRI agent.