Introduction

The cornerstone of a technologist’s responsibility is to produce consistently high-quality examinations while ensuring the safety and well-being of patients. Educational content for the CT technologist must be evaluated with that goal in mind. It is not necessary that a technologist’s understanding of CT physics rival that of a medical physicist. I believe in the concept expressed in the phrase, “You don’t have to know how to build a car to be a good driver.”

However, understanding the physical aspects of CT technology allows the technologist to identify deficiencies in images and to take appropriate corrective actions, just as understanding the basics of auto mechanics will help a driver know whether their car simply needs gas or whether a trip to the repair shop is warranted.

The physics presented in this section will allow technologists to move past the rote learning of examination protocols and grasp why we do what we do. They will understand the connection between the choices they make when selecting scan parameters and the radiation dose delivered to the patient. It will not prepare them for a career as a physicist. For those readers who desire a more in-depth understanding of CT physics, there are many textbooks from which to choose.