ABSTRACT
This chapter provides a concise list of the most important theoretical and practical elements involved in Computed Tomography (CT) and Positron Emission Tomography (PET) reconstruction, along with a brief description for each of them. It is mandatory for the readers who are still at the preliminary stage of their study in PET/CT technology and reconstruction. Analytical methods treat both images and projections as continuous functions. The process of image acquisition is ideally represented as a linear and continuous operator acting on the space of object functions representing the patient (or object) under examination. Hence, the acquisition process gives rise to a integral transform of the unknown function describing the patient; image reconstruction must be carried out by inverting an integral transform.
