Coordinate systems

Introduction

One of the great issues while dealing with medical images and applications are the differences between the coordinate systems. There are three coordinate systems commonly used in medical applications: a difference can be made between the world, anatomical and the image coordinate system.

The following figure illustrates the three spaces with their corresponding axes:

Each coordinate system serves one purpose and represents their data in different ways: The world coordinate system is typically a Cartesian coordinate system in which a model (e.g. a MRI scanner or a patient) is positioned. Every model has its own coordinate system but there is only one world coordinate system to define the position and orientation of each model.