Intracranial Gadolinium Deposition-From the Journals

• Gadolinium-based contrast agents (GBCAs) represent a family of aminopolycarboxylic acid ligands chelated to gadolinium, a rare earth metal capable of altering the relaxivity of nearby water molecules by means of interaction with its unpaired electrons.
• As free gadolinium is cytotoxic, the presence of the organic ligand serves as a physiologic chaperone, allowing an otherwise toxic metal to be safely administered intravenously and excreted.
• Despite relatively uncomplicated initial clinical trials in the early 1990s, a 2006 study causally associated the administration of gadolinium with the development of nephrogenic systemic fibrosis in patients with pre-existing renal dysfunction. 
• An article published in Radiology in 2015  showed Elemental gadolinium accumulates in neuronal tissues after intravenous administration of gadolinium-based contrast agents (GBCAs), even in patients with normal renal and hepatobiliary function.
• The clinical significance of these findings is incompletely understood at this time.

Reference 

Intracranial Gadolinium Deposition after Contrast-enhanced MR Imaging

Robert J. McDonald, Jennifer S. McDonald, David F. Kallmes, Mark E. Jentoft, David L. Murray, Kent R. Thielen, Eric E. Williamson, and Laurence J. Eckel

Radiology 2015 275:3, 772-782 

DOI: http://dx.doi.org/10.1148/radiol.15150025