Overall, ten publications met the selection criteria for this review and included: two systematic reviews, six randomized controlled trials, and two non-randomized clinical studies. Three of the included studies examined the risks and safety of macrocyclic gadolinium-based contrast agents, including gadobutrol and gadoteridol. All three studies reported that these contrast agents were well-tolerated with a good safety profile. Two studies examined the risks and safety of linear gadolinium-based contrast agents, including gadodiamide, gadopentetate dimeglumine and gadoxetate disodium. One study found that that gadopentetate dimeglumine had no nephrotoxic effects, and gadodiamide had slight, though clinically insignificant, nephrotoxic effects. The second study, comparing the safety of gadoxetate disodium and gadobenate dimeglumine, found that both agents had a similar safety profile, with approximately 6% of patients in both groups experiencing adverse events. Five of the included studies, including a meta-analysis, a systematic review, and three randomized controlled trials, provided a comparison of the risks and safety of macrocyclic and linear gadolinium-based contrast agents. The meta-analysis found that protein binding, macrocyclic structure, and ionicity were associated with a higher rate of allergic-like adverse events in patients injected with gadolinium-based contrast agents. The systematic review reported that signal intensity on unenhanced T1-weighted magnetic resonance images was positively correlated with exposure to gadolinium-based contrast agents, and this was greater after serial administrations of linear nonionic versus cyclic contract agents. Finally, three randomized control trials found both macrocyclic and linear gadolinium-based contrast agents were well tolerated.