DSA | Laboratoire d’Ingénierie Moléculaire Appliquée à l’Analyse (LIMAA) » Research Interests » Mini lexicon » Magnetic Resonance Imaging
Dernière mise à jour : lundi 29 août 2011, par
Magnetic resonance imaging is perhaps the most widely used non-invasive medical imaging technique. Physical principles of MRI rely on the monitoring of the distribution and properties of water in the examined tissue.
More specifically, the image contrast is generated from the variation of the nuclear magnetic resonance characteristics of water protons (their longitudinal and transverse relaxation times T1 and T2) when exposed to an external magnetic field.
Because of its high spatial resolution (40 μm – 1 mm), MRI is mainly used for the assessment of anatomic changes but its application in limited by its low sensitivity (μM-mM). Paramagnetic and superparamagnetic contrast agents have been developed : Gadolinium(III) complexes and to a lesser extent, Manganese(II) chelates and Iron-based nanoparticles.