Biomedical Imaging: Principles and Applications

Chapter 5

Magnetic Resonance Technology

Boguslaw Tomanek and Jonathan C. Sharp

Institute for Biodiagnostics (West), National Research Council of Canada, Calgary, AB, Canada

5.1 Introduction

Magnetic resonance technology comprises the hardware, software, and imaging techniques used in Magnetic Resonance Imaging (MRI) and Magnetic Resonance Spectroscopy (MRS). MRI has become one of the most useful imaging techniques used in medical diagnosis. Thousands of MRI systems have been produced and installed in clinics since the first introduction to hospitals in the early 1980s. In recognition of the importance of MRI to the practice of medicine, Dr Paul Lauterbur and Sir Peter Mansfield were awarded the 2003 Nobel Prize in Medicine for their discoveries concerning MRI. The Nuclear Magnetic Resonance (NMR) phenomenon, on which MRI is based, was discovered in 1945 by Purcell, Torrey, and Pound at Harvard (1) and independently by Bloch, Hansen, and Packard at Stanford (2). This followed the discovery of electron paramagnetic resonance by J. Zawoysky in 1944. Their work was continued by Hahn (3), who discovered the Spin Echo (SE), and Gabillard (4, 5), who showed that a magnetic field gradient can be used to obtain the spatial distribution of a sample of spins. These discoveries were used exclusively in chemistry until the 1950s, when NMR began to find an application in medicine with the discovery of the relationship between relaxation times and water content in tissue. This was confirmed by ...