ABSTRACT
Small molecular weight paramagnetic contrast agents that diffuse from the vascular to extravascular space are routinely used in magnetic resonance imaging (MRI) to improve contrast between healthy and diseased tissue. Since attaining FDA approval in 1988, gadoliniumbased contrast agents, in particular, have facilitated major improvements in the sensitivity of detection, delineation, and characterization of cancer using MRI [1,2]. Paramagnetic contrast agents increase the relaxivity of proximal water protons, shortening their apparent T1 and T2. Accumulation of contrast agent in a tissue will reduce the observed signal in a T2-or T2*-weighted image while increasing or enhancing the observed signal on a T1-weighted image.
