Basic physics of MR contrast agents and maximization of image contrast

This review summarizes the physical basis of magnetic resonance (MR) imaging contrast agents, including both T1 agents, such as gadolinium-DTPA (diethylenetriaminepentaacetic acid), and T2 or T2* agents, such as superparamagnetic iron oxides. The maximization of image contrast and lesion visibility with contrast agents is described, and the use of contrast agents in MR angiography and perfusion imaging is discussed.