All of them are gadolinium based chelates.Those which have high relaxivity

have higher diagnostic efficacy and smaller dose is required to achieve optimal

enhancement compared to ones which have lower relaxivity. Those which are

chemically stabler are clinically safer.Theoretically non ionic low osmolar agents

seem to be safer, in practice however,ionic agents are equally safe.

Macrocyclics are safer options compared to linears .Three molecules are available among macrocyclics:

*Gadoterate(Dotarem-Guebert),gadoteridol(ProHance-Bracco) and gadobutrol(Gadovist-Bayer).

*In no particular order.