Spatial encoding and image reconstruction

Abstract

In order to form images with the required resolution and anatomical coverage, gradient magnetic fields are used to excite magnetization in a predefined slice or slab, with subsequent spatial encoding to obtain spatial resolution in the slice or slab. It is demonstrated how the spatial encoding principle is implemented and how it can be conceptualized using the so-called k-space representation. The relations between the field of view, spatial resolution, and k-space sampling are illustrated, along with the implementation using a simple pulse sequence. Once magnetic resonance data have been collected in k-space, the process of image reconstruction will yield the final images.