The Emerging Role of USPIOs for MR Imaging of Atherosclerosis
Atherosclerosis is an inflammatory disease of the arteries, which causes more than 19 million deaths worldwide every year. Most complications of atherosclerosis are caused by rupture of a vulnerable plaque. Currently, there are no imaging techniques available in clinical practice that can accurately identify a vulnerable plaque. There is an emerging role for Ultrasmall Super-paramagnetic Iron Oxide Particles (USPIOs) in MR imaging of atherosclerosis. This review will first give an update on the biology of atherosclerosis. Next, we will focus on the physicochemical properties of USPIOs and describe animal and human studies that showed USPIO uptake mainly in macrophages of atherosclerotic plaque, which could be detected as areas of focal signal loss in MR images. Novel superparamagnetic particles are currently being developed which enable visualization of other cell types and functions than macrophage uptake that are relevant for atherosclerosis. We conclude that USPIOs are a highly promising imaging tool for atherosclerosis and larger prospective studies are warranted to prove the value in daily clinical practice.
KeywordsAtherosclerotic Plaque Vulnerable Plaque Superparamagnetic Iron Oxide Iron Oxide Particle Superparamagnetic Iron Oxide Particle
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- Briley-Saebo, K.C., Mani, V., Hyafil, F., et al., 2006. Positive contrast MR imaging of in vivo atherosclerosis in a rabbit model using ultrasmall iron oxide particles. Proc. Intl. Soc. Mag. Reson. Med. 14, 563.Google Scholar
- Dahnke, H., Liu, W., Frank, J., et al., 2006. Optimal positive contrast of labeled cells via conventional 3D imaging. Proc. Intl. Soc. Mag. Reson. Med. 14, 361.Google Scholar
- Litovsky, S., Madjid, M., Zarrabi, A., et al., 2003. Superparamagnetic iron oxide-based method for quantifying recruitment of monocytes to mouse atherosclerotic lesions in vivo: enhancement by tissue necrosis factor-alpha, interleukin-1beta, and interferon-gamma. Circulation 107, 1545–1549.PubMedCrossRefGoogle Scholar
- Mani, V., Briley-Saebo, K.C., Itskovich, V.V., et al., 2006. Gradient echo acquisition for superparamagnetic particles with positive contrast (GRASP): sequence characterization in membrane and glass superparamagnetic iron oxide phantoms at 1.5T and 3T. Magn Reson Med 55, 126–135.PubMedCrossRefGoogle Scholar
- Mauriello, A., Sangiorgi, G., Fratoni, S., et al., 2005. Diffuse and active inflammation occurs in both vulnerable and stable plaques of the entire coronary tree: a 5. Emerging Role of USPIOs for Imaging of Atherosclerosis 89 histopathologic study of patients dying of acute myocardial infarction. J Am Coll Cardiol 45, 1585–1593.PubMedCrossRefGoogle Scholar
- Pande, A.N., Kohler, R.H., Aikawa, E., et al., 2006. Detection of macrophage activity in atherosclerosis in vivo using multichannel, high-resolution laser scanning fluorescence microscopy. J Biomed Opt 11, 21009.Google Scholar