Computerized tomography (CT) imaging after intravenous injection of a novel contrast agent detected macrophages in atherosclerotic plaques of rabbits in a study appearing in the May issue of Nature Medicine.

The contrast agent, formed of iodinated nanoparticles dispersed with surfactant, "may become an important adjunct to the clinical evaluation of coronary arteries with CT," the study said.

The authors said that a "major hurdle" in detecting high-risk atherosclerotic plaques in arteries is the lack of an imaging modality to identify atherosclerotic plaque composition with high spatial and temporal resolutions.

Early identification of high-risk plaques may be useful for preventing ischemic events, the authors added.