MRI contrast agent for use in the diagnosis of early changes in the endothelium of blood vessels

An MRI contrast agent for use in the diagnosis of early changes in blood vessel endothelium, in the form of an aqueous suspension containing as a hydrophilic contrast agent Gd-diethylenetriaminepentaacetate-bis (methylamide) encapsulated within single-layer liposomes from 50 nm to 200 nm in size, wherein the lipid membrane of the liposomes is made of a mixture containing:

• purified phosphatidylcholine that has not been hydrogenated, cholesterol and polyethylene glycol covalently bounded to a phosphatidylethanolamine molecule (PEG-PE) to lengthen circulation of liposomes in the bloodstream.