The development of magnetic resonance imaging (MRI) for use in medical investigation has provided a huge forward leap in the field of diagnosis, particularly with avoidance of exposure to potentially dangerous ionizing radiation. With decreasing costs and better availability, the use of MRI is becoming ever more pervasive throughout clinical practice. Understanding the principles underlying this imaging modality and its multiple applications can be used to appreciate the benefits and limitations of its use, further informing clinical decision-making. In this article, the principles of MRI are reviewed, with further discussion of specific clinical applications such as parallel, diffusion-weighted, and magnetization transfer imaging. MR spectroscopy is also considered, with an overview of key metabolites and how they may be interpreted. Finally, a brief view on how the use of MRI will change over the coming years is presented.
Keywords: ADC, apparent diffusion coefficient; CSI, Chemical shift imaging; DTI, diffusion tensor imaging; DWI, Diffusion-weighted imaging; FA, Fractional anisotropy; FID, free induction decay; MRI, magnetic resonance imaging; MTR, MT ratios; NMR, nuclear magnetic resonance; PRESS, Point-resolved spectroscopy; RA, relative anisotropy; RF, radiofrequency; SNR, signal-to-noise ratio; STEAM, Stimulated echo acquisition mode; TR, repetition time; magnetic resonance imaging; magnetic resonance spectroscopy; medical physics; nuclear magnetic resonance; nuclear medicine.