Basic principles of MRI

Abstract

Magnetic resonance imaging (MRI) is the imaging modality of choice for the evaluation of a variety of musculoskeletal pathologies. MRI has the advantage that it does not use ionising radiation and is non-invasive. In addition, it has a high soft tissue resolution and imaging capabilities in multiple planes. A detailed knowledge of nuclear physics is not required for the interpretation of MRI images in the clinical setting. However, a basic understanding of the principles of MRI physics will allow the physician to understand the MRI appearances of pathological processes, identify abnormalities and make appropriate referrals for MRI investigations. This chapter briefly reviews the basics of MRI physics at a nuclear level, the steps involved in image acquisition, the pros and cons of various sequences for evaluating different tissue types and pathologies. We discuss MRI safety and future applications of MRI.