Overview

Abstract

The study of the physics of magnetic resonance imaging (MRI) can be partitioned into two major areas: (1) the study of how we obtain tissue contrast- i.e.: what makes one tissue appear brighter than another; and (2) the study of how the signals produce an image in space- i.e.: what the pattern of these different intensities is. We will study both of these subjects in just that order. We must be careful to realize that this division is an arbitrary device that we are using to better conceptualize the physics of MRI. In reality, the two areas of study represent a relatively integrated unit; and in fact, there will be times when we must cross the “border” from one division to the other when considering certain topics. This will become clearer as we proceed, so let us begin with the first area: how we create tissue contrast in MRI.