This edition first published 2018

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Library of Congress Cataloging-in-Publication Data

Names: Seeram, Euclid, author.

Title: CT at a glance / Euclid Seeram, PhD., MSc., BSc., FCAMRT.

Description: Hoboken, NJ : John Wiley & Sons, 2017. | Includes index. |

Identifiers: LCCN 2017025967 (print) | LCCN 2017040984 (ebook) | ISBN

9781118660881 (pdf) | ISBN 9781118660898 (epub) | ISBN 9781118660904 (pbk.)

Subjects: LCSH: Tomography.

Classification: LCC RC78.7.T6 (ebook) | LCC RC78.7.T6 S3715 2017 (print) |

DDC 616.07/57—dc23

LC record available at https://lccn.loc.gov/2017025967

Cover image: © Phil Boorman/Gettyimages

Cover design by Wiley

Foreword

Dr Euclid Seeram is a distinguished and rigorous academic who has a proven track record in providing understandable and comprehensive radiological manuscripts. He has decades of experience in the teaching of CT physical principles and medical imaging sciences.

A hallmark of his approach is the ability to convey complex topics in an easy-to-read and manageable way, and this work is no exception. He presents his topics in an organized, progressive, and comprehensive manner so that at the end of each clearly defined chapter, learning objectives are met and the reader comes away with a solid and supported knowledge of specific topics. Euclid has decades of experience in the teaching of CT and medical imaging, and during this time has gained worldwide respect as an educator. Both clinicians and physicists in the field of medical imaging are in agreement with the high level of influence Euclid has on medical imaging education and on the profession as a whole. He is simply a global leader in his field. Euclid’s published works have made an impact on radiologic science and technology education, and in particular computed tomography (CT).

This book, CT at a Glance, is another means of bringing an understanding of CT to radiographers, radiologic technologists, and others interested in CT physical principles. The technical and clinical developments of CT have continued over recent years and its use in medicine has proven that it is significant and an important diagnostic imaging tool for clinicians to aid in their diagnosis. CT at a Glance provides an easy understanding of this complex diagnostic imaging modality.

Euclid must be commended for his continued efforts in making CT and other medical imaging technical knowledge easy to understand by students and clinicians.

Rob Davidson, PhD, MAppSc (MI), BBus, FIR

Professor in Medical Imaging

Head, Discipline of Medical Radiations

University of Canberra

Canberra, Australia

Preface

Computed tomography (CT) has experienced significant technological advances ever since its invention in the early 1970s. These advances are meant to improve the scanning speed and reduce the dose to the patient without compromising the diagnostic quality of the image. A few of these significant and important advances include scanners that can image multiple slices in a single breath-hold (multislice CT systems), new detector technologies, automatic exposure control (tube current modulation), automatic voltage selection (X-ray spectra optimization), X-ray beam collimation strategy, iterative reconstruction algorithms that enable scanning at significantly lower doses while maintaining image quality, dual-energy CT scanners that can image the beating heart with excellent detail, and dose optimization strategies, to mention but a few.

The book describes the physical basis for CT and focuses on theory that is essential for practice. Educationally it is pitched at the entry-level for radiographers and radiological technologists, focusing on fundamental physics and technical principles. The main feature of this book is that it provides alternative descriptions of existing knowledge, through the use of multiple illustrations to describe the essential knowledge base for understanding CT physics and instrumentation. Already various radiography organizations such as the American Society of Radiological Technologists (ASRT) and the Canadian Association of Medical Radiation Technologists (CAMRT) have introduced selected topics in Computed Tomography (CT) for what they label as “entry-to-practice” requirements. The purpose of this text is to meet these requirements, and those of other professional organizations for radiographers and radiological technologists in other parts of the world. This book will serve as a resource for entry-to-practice students in medical imaging technologies such as radiography, nuclear medicine, and radiation therapy. Furthermore, this book can also be used by biomedical engineering technology students studying CT physical principles, CT image quality and quality control as well as radiation protection in CT.

The content and organization are based on 24 chapters ranging from historical perspectives, basic physics concepts, multislice technologies, data acquisition strategies, equipment components, image reconstruction, and image quality considerations to CT dose and dose optimization procedures, and quality control fundamentals.

Read on, learn, and enjoy. Your patients will benefit from your wisdom