Gadolinium deposition in the brain: current knowledge and recommendations

Gadolinium based contrast agents (GBCAs) have been widely used intravenously in MRI examinations and are considered relatively safe in patients with intact renal function. However, since 2014, repeated administrations of GBCAs have been associated to high MRI signal intensity in deep brain nuclei, on unenhanced T1-weighted images, a finding that has been attributed to gadolinium (Gd) parenchymal deposition. Deep brain nuclei Gd deposition is variable among different agents available for clinical practice and is considered greater with linear GBCAs compared to macrocyclic agents. The clinical significance of Gd brain retention has not been extensively studied and remains, to a great extent, undetermined. In this review article, the biochemical structure of GBCAs, the clinical and pathologic studies investigating morphological and histological changes after multiple intravenous Gd administration, the suggested pathogenetic mechanisms and the recent recommendations towards safe use of these agents are summarised.