Artifacts Reduction Techniques in X-ray Cone-beam Computed Tomography Reconstruction PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Artifacts Reduction Techniques in X-ray Cone-beam Computed Tomography Reconstruction PDF full book. Access full book title Artifacts Reduction Techniques in X-ray Cone-beam Computed Tomography Reconstruction by Bowen Meng. Download full books in PDF and EPUB format.
Author: Bowen Meng
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
CBCT is an important tool in image guided radiation therapy. With the existing reconstruction methods, however, various artifacts arise in the image, which are caused by under-sampled projection data, large-area detector, and/or presence of metal implants in patients. This dissertation addresses issues for improved CBCT image quality and clinical decision making. In practical CBCT systems, a circular trajectory is commonly used to acquire projections and reconstruct the volume. However, incomplete data might be collected in a short scan either because of mechanical constraint or dose reduction consideration. In such situation, FDK algorithm cannot provide an accurate image due to the theoretical limitation. In this dissertation, an iterative optimization using prior knowledge and rigid image registration is proposed to handle the limited angle reconstruction problem. The algorithm is derived based on the prior image constrained compressed sensing (PICCS) framework. The proposed algorithm is experimentally validated and compared with PICCS algorithm and demonstrates superior reconstruction accuracy. Large-area flat panel detector induces more scatter, which results in cupping and shading artifacts in the images. Various scatter correction methods have been proposed to reduce the artifacts from both hardware and software sides, but still suffer clinical applicability. In this dissertation, a single-scan scatter correction method using periphery scatter detection and compressed sensing technique is proposed and tested. The algorithm integrates the scatter measurement/reconstruction and projection acquisition into one scan with simple design of boundary lead blockers. It shows effective scatter artifacts reduction ability as well as promising practical usage for the existing CBCT systems. The presence of metals in patients may cause streaking artifacts in x-ray CT, which has long been recognized as a problem that not only limits the quality of CT images, but also makes dose calculation in radiation therapy planning problematic. In this dissertation, a method for binary reconstruction of metal objects is proposed to serve as the first step of metal artifacts reduction. The boundaries of metallic objects are obtained by using a penalized weighted least-squares algorithm with the adequate intensity gradient-controlled. A series of experimental studies are performed to evaluate the proposed approach, and show that when the projection data are sparse, a non-linear manipulation of projection data can greatly facilitate the binary reconstruction process to achieve accurate binary CT images.
Author: Bowen Meng
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
CBCT is an important tool in image guided radiation therapy. With the existing reconstruction methods, however, various artifacts arise in the image, which are caused by under-sampled projection data, large-area detector, and/or presence of metal implants in patients. This dissertation addresses issues for improved CBCT image quality and clinical decision making. In practical CBCT systems, a circular trajectory is commonly used to acquire projections and reconstruct the volume. However, incomplete data might be collected in a short scan either because of mechanical constraint or dose reduction consideration. In such situation, FDK algorithm cannot provide an accurate image due to the theoretical limitation. In this dissertation, an iterative optimization using prior knowledge and rigid image registration is proposed to handle the limited angle reconstruction problem. The algorithm is derived based on the prior image constrained compressed sensing (PICCS) framework. The proposed algorithm is experimentally validated and compared with PICCS algorithm and demonstrates superior reconstruction accuracy. Large-area flat panel detector induces more scatter, which results in cupping and shading artifacts in the images. Various scatter correction methods have been proposed to reduce the artifacts from both hardware and software sides, but still suffer clinical applicability. In this dissertation, a single-scan scatter correction method using periphery scatter detection and compressed sensing technique is proposed and tested. The algorithm integrates the scatter measurement/reconstruction and projection acquisition into one scan with simple design of boundary lead blockers. It shows effective scatter artifacts reduction ability as well as promising practical usage for the existing CBCT systems. The presence of metals in patients may cause streaking artifacts in x-ray CT, which has long been recognized as a problem that not only limits the quality of CT images, but also makes dose calculation in radiation therapy planning problematic. In this dissertation, a method for binary reconstruction of metal objects is proposed to serve as the first step of metal artifacts reduction. The boundaries of metallic objects are obtained by using a penalized weighted least-squares algorithm with the adequate intensity gradient-controlled. A series of experimental studies are performed to evaluate the proposed approach, and show that when the projection data are sparse, a non-linear manipulation of projection data can greatly facilitate the binary reconstruction process to achieve accurate binary CT images.
Author: Jiang Hsieh
Publisher: Society of Photo Optical
ISBN: 9780819475336
Category : Medical
Languages : en
Pages : 556
Get Book Here
Book Description
X-ray computed tomography (CT) continues to experience rapid growth, both in basic technology and new clinical applications. Seven years after its first edition, Computed Tomography: Principles, Design, Artifacts, and Recent Advancements, Second Edition, provides an overview of the evolution of CT, the mathematical and physical aspects of the technology, and the fundamentals of image reconstruction algorithms. Image display is examined from traditional methods used through the most recent advancements. Key performance indices, theories behind the measurement methodologies, and different measurement phantoms in image quality are discussed. The CT scanner is broken down into components to provide the reader with an understanding of their function, their latest advances, and their impact on the CT system. General descriptions and different categories of artifacts, their causes, and their corrections are considered at length. Given the high visibility and public awareness of the impact of x-ray radiation, the second edition features a new chapter on x-ray dose and presents different dose reduction techniques ranging from patient handling, optimal data acquisition, image reconstruction, and post-process. Based on the advancements over the past five years, the second edition added new sections on cone beam reconstruction algorithms, nonconventional helical acquisition and reconstruction, new reconstruction approaches, and dual-energy CT. Finally, new to this edition is a set of problems for each chapter, providing opportunities to enhance reader comprehension and practice the application of covered material.
Author: Shuai Leng
Publisher:
ISBN:
Category :
Languages : en
Pages : 160
Get Book Here
Book Description
Author: Chris C. Shaw
Publisher: Taylor & Francis
ISBN: 143984626X
Category : Medical
Languages : en
Pages : 272
Get Book Here
Book Description
Conventional computed tomography (CT) techniques employ a narrow array of x-ray detectors and a fan-shaped x-ray beam to rotate around the patient to produce images of thin sections of the patient. Large sections of the body are covered by moving the patient into the rotating x-ray detector and x-ray source gantry. Cone beam CT is an alternative technique using a large area detector and cone-shaped x-ray beam to produce 3D images of a thick section of the body with one full angle (360 degree or 180 degree plus detector coverage) rotation. It finds applications in situations where bulky, conventional CT systems would interfere with clinical procedures or cannot be integrated with the primary treatments or imaging systems. Cone Beam Computed Tomography explores the past, present, and future state of medical x-ray imaging while explaining how cone beam CT, with its superior spatial resolution and compact configuration, is used in clinical applications and animal research. The book: Supplies a detailed introduction to cone beam CT, covering basic principles and applications as well as advanced techniques Explores state-of-the-art research and future developments while examining the fundamental limitations of the technology Addresses issues related to implementation and system characteristics, including image quality, artifacts, radiation dose, and perception Reviews the historical development of medical x-ray imaging, from conventional CT techniques to volumetric 3D imaging Discusses the major components of cone beam CT: image acquisition, reconstruction, processing, and display A reference work for scientists, engineers, students, and imaging professionals, Cone Beam Computed Tomography provides a solid understanding of the theory and implementation of this revolutionary technology.
Author: Andreas Maier
Publisher: Springer
ISBN: 3319965204
Category : Computers
Languages : en
Pages : 263
Get Book Here
Book Description
This open access book gives a complete and comprehensive introduction to the fields of medical imaging systems, as designed for a broad range of applications. The authors of the book first explain the foundations of system theory and image processing, before highlighting several modalities in a dedicated chapter. The initial focus is on modalities that are closely related to traditional camera systems such as endoscopy and microscopy. This is followed by more complex image formation processes: magnetic resonance imaging, X-ray projection imaging, computed tomography, X-ray phase-contrast imaging, nuclear imaging, ultrasound, and optical coherence tomography.
Author: Manuel Meilinger
Publisher: Universitatsverlag Regensburg
ISBN: 9783868450743
Category :
Languages : en
Pages : 118
Get Book Here
Book Description
Author: Yulia Levakhina
Publisher: Springer
ISBN: 3658056975
Category : Computers
Languages : en
Pages : 205
Get Book Here
Book Description
Yulia Levakhina gives an introduction to the major challenges of image reconstruction in Digital Tomosynthesis (DT), particularly to the connection of the reconstruction problem with the incompleteness of the DT dataset. The author discusses the factors which cause the formation of limited angle artifacts and proposes how to account for them in order to improve image quality and axial resolution of modern DT. The addressed methods include a weighted non-linear back projection scheme for algebraic reconstruction and novel dual-axis acquisition geometry. All discussed algorithms and methods are supplemented by detailed illustrations, hints for practical implementation, pseudo-code, simulation results and real patient case examples.
Author: Avinash C. Kak
Publisher: SIAM
ISBN: 089871494X
Category : Mathematics
Languages : en
Pages : 335
Get Book Here
Book Description
A comprehensive, tutorial-style introduction to the algorithms necessary for tomographic imaging.
Author: Mathias Prokop
Publisher: Thieme
ISBN: 3131607114
Category : Medical
Languages : en
Pages : 1892
Get Book Here
Book Description
Whole body computed tomography has developed at a rapid pace in the past decade, spurred on by the introduction of spiral and multislice scanning. These new technologies have not only improved diagnostic accuracy, but also made new applications possible that were previously accessible only through more complex or invasive techniques.This new book expertly fills a gap in the literature by combining the practically relevant technical background with the clinical information required for correctly performing and interpreting CT examinations. The book presents the state-of-the-art capabilities and requirements of CT as a key diagnostic and interventional tool, with special emphasis on the role of spiral and multi-slice CT. You will find a thorough introduction to CT technology from scanner design to 3D image reconstruction, useful practical hints on how to optimize your examination protocols and how to keep the radiation exposure of your patients to a minimum, as well as an extensive clinical section in which symptoms, pathology and CT morphology are integrated to provide you withthe basis for subtle interpretation of CT findings using the most modern CT techniques.Highlights include:- Full coverage of single-slice, 4-slice and 16-slice scanning techniques- Introduction to extended CT applications including cardiac CT,CT fluoroscopy,and 3D image processing- Organ-specific protocols for scanning and contrast administration- Practical guidelines for maximizing image quality and minimizing radiation exposure- Useful suggestions for image interpretation and for avoiding pitfalls and errors- Convenient format by organ systemand disease entity- Full discussion of organ-specific pathology and CT morphology- CT indications integrated with other imaging modalitiesAt a time when CT examinations are becoming more technically demanding and complex, with an increasing number of scan parameters and advances in 3D reconstructions, this book is an essential professional tool. Experienced practitioners will find their diagnostic and technical skills improved by reading the book, and beginners will enjoy the clear, systematic approach that will help them use the technique with confidence.
Author: Simone Carmignato
Publisher: Springer
ISBN: 3319595733
Category : Technology & Engineering
Languages : en
Pages : 372
Get Book Here
Book Description
X-ray computed tomography has been used for several decades as a tool for measuring the three-dimensional geometry of the internal organs in medicine. However, in recent years, we have seen a move in manufacturing industries for the use of X-ray computed tomography; first to give qualitative information about the internal geometry and defects in a component, and more recently, as a fully-quantitative technique for dimensional and materials analysis. This trend is primarily due to the ability of X-ray computed tomography to give a high-density and multi-scale representation of both the external and internal geometry of a component, in a non-destructive, non-contact and relatively fast way. But, due to the complexity of X-ray computed tomography, there are remaining metrological issues to solve and the specification standards are still under development. This book will act as a one-stop-shop resource for students and users of X-ray computed tomography in both academia and industry. It presents the fundamental principles of the technique, detailed descriptions of the various components (hardware and software), current developments in calibration and performance verification and a wealth of example applications. The book will also highlight where there is still work to do, in the perspective that X-ray computed tomography will be an essential part of Industry 4.0.
