X-ray computed tomography (CT) has experienced an explosion of technological development for a quarter century. Six years after the second edition of Computed Tomography, this third edition captures the most recent advances in technology and clinical applications. New to this edition are descriptions of iterative reconstruction, statistical reconstruction, methodologies used to model the CT systems, and the searching methodologies for optimal solutions. A new section on 3D printing introduces approaches by early adopters in the area. Also added is a description and discussion of the size-specific dose estimate, an index that attempts to more accurately reflect the dose absorption of specific-sized patients. The coverage of dual-energy CT has been significantly expanded to include its background, theoretical development, and clinical applications.

"This is a new edition of the reputable book on the principles and designs of CT, which I believe is the best CT textbook available. The new materials appropriately cover the emerging field with sufficient depth, further increasing the value of the book."
--Katsuyuki (Ken) Taguchi, Ph.D., Johns Hopkins University School of Medicine

Want a more thorough understanding? Use this book along with the author's online course: Principles and Advancements in X-ray Computed Tomography: SC471

X-ray computed tomography (CT) has experienced a tremendous explosion in technological development over the last quarter century, a phenomenon rarely seen in industry. Few could have predicted the speed, magnitude, and duration of the progress. The third edition of Computed Tomography captures the most recent advances in technology and clinical applications.

This third edition provides significant additions in several areas. The first area of major enhancement is on the topic of iterative reconstruction. With the heightened awareness of radiation dose in CT in recent years, iterative reconstruction has evolved from a topic in academic research to the mainstream of CT reconstruction for all commercially available scanners. Chapter 3 describes the fundamental concept of iterative reconstruction, the idea of statistical reconstruction, methodologies used to model CT systems, and searching methodologies for optimal solutions. Given the clinical demands on workflow, a brief discussion on the reconstruction speedup effort is also provided.

One complexity brought by the iterative reconstruction technology is performance evaluation. Unlike the filtered backprojection reconstruction algorithm, in general, iterative reconstruction performance is nonlinear. Although some of the existing measurement approaches are still useful, they are inadequate to fully assess the performance of iteratively reconstructed images. Chapter 5 has an added section that discusses the impact and various measurement methodologies of iterative reconstruction.

Historically, the presentation of the CT outcome has been limited to computer monitors, either at scanner consoles, workstations, or PACS monitors. With the recent advancements in 3D printing, however, physical models can be quickly prototyped to convey CT information. Therefore, a section was added in Chapter 4 to introduce approaches by the early adopters in the area.

In terms of radiation dose, the topic of a size-specific dose estimate (SSDE) has been added. During the last few years, significant attention has been paid to the radiation impact on human health by academic researchers, radiologists, the general public, and the news media. Although awareness on the subject has been increasing, dose measurement methodology was xi developed more than a decade ago. The updated Chapter 11 briefly describes the recent proposal of a dose measurement index, SSDE, in an attempt to more accurately reflect the dose absorption rates of specific-sized patients, and proposed modifications to the dose measurement for scanners with large z coverage.

When the second edition of this book was published, true cone-beam CT had just been introduced commercially. Nowadays, scanners capable of single-organ coverage in a rotation are widely available commercially and have significantly impacted clinical practices. Chapter 10 has been expanded to discuss the technological challenges associated with wide-cone step-and-shoot reconstruction and the additional challenges with cardiac imaging.

Dual-energy CT was predominately in the hands of a few researchers at the time of the second edition publication. The situation has significantly changed since then, as dual-energy CT is now utilized in routine clinical applications to aid in disease diagnosis. A significant expansion to Chapter 12 has been written to provide the technology background, theoretical development, and clinical applications of dual-energy CT.

To enhance readers’ understanding of the material and to inspire creative thinking about the topics presented, more problems have been added at the end of each chapter. Many problems are open-ended and may not have uniquely correct solutions.

At the time of the publication of the second edition, the world was experiencing an unprecedented financial crisis that some called a financial "tsunami." Although we predicted that “CT technology is unlikely to remain stagnant,” nobody was certain about the true impact the crisis would have on CT development. Recent advances in CT have shown that the entire industry remains healthy, and the demand for advanced CT technologies has expanded beyond the developed counties. The future of CT remains bright.

Jiang Hsieh
July 2015