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Basic Res Cardiol 103:152160 (2008) DOI 10.1007/s00395-008-0706-3
REVIEW
Ren M. Botnar Eike Nagel Structural and functional imaging by MRI
j Abstract Magnetic resonance imaging is one of the most exciting techniques for noninvasive molecular imaging of the cardiovascular system. The article will describe challenges, solutions and results of magnetic resonance plaque imaging ex-vivo, in the experimental animal and in patients.
j Key words magnetic resonance plaque imaging molecular imaging coronary artery disease
R.M. Botnar, PhDDept. of Nuclear Medicine Klinikum Rechts der Isar, Technische Universitat MnchenMunich, Germany
E. Nagel, MD Techniques for Biomedical Imaging Technical University BerlinBerlin, Germany
Introduction
Magnetic resonance imaging is one of the most exciting techniques for noninvasive molecular imaging of the cardiovascular system. It has several characteristics, which make it highly suitable for this purpose. Its ability to visualize uids, with both high and low signal allows for noninvasive angiography (white blood imaging) or vessel wall imaging (black blood imaging), making it a unique tool for vascular applications. Due to its excellent tissue contrast, it allows us to discriminate between different parts of the vessel wall or plaque. In principle MRI can yield very high spatial resolution images, and may yield information similar to histology [14]. MRI is not limited by imaging windows, problematic tissue penetration or radiation. In addition, it can be used not only to visualize and characterize different components of the plaque and the vessel wall but also to detect functional parameters such as endothelial function or plaque activity such as inammation and neoangiogenesis. It may thus emerge as a tool for early and individual risk assessment.
The following article will describe challenges, solutions and results of magnetic resonance plaque imaging ex-vivo, in the experimental animal and in
patients. The use of specic contrast agents will not be discussed here; instead, they will be described in detail by Waters and Sosnovik elsewhere in this issue.
Signal-to-noise ratio
With current MR systems and sequences, the signal-to-noise ratio required for an accurate visualization and characterization of plaques within the coronary arteries has not yet been achieved with current eld strengths(1.5 Tesla), receiver coils, and sequences. Other limitations are a suboptimal suppression of breathing motion artifacts and the lack of contrast agents, which achieve a sufcient local concentration to allow for robust...