Download or read book Characterisation and Correction of Respiratory motion Artefacts in Cardiac PET CT written by S. McQuaid and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Respiratory motion during cardiac Positron Emission Tomography (PET) Computed Tomography (CT) imaging results in blurring of the PET data and can induce mismatches between the PET and CT datasets, leading to attenuation-correction artefacts. The aim of this project was to develop a method of motion-correction to overcome both of these problems. The approach implemented was to transform a single CT to match the frames of a gated PET study, to facilitate respiratory-matched attenuation-correction, without the need for a gated CT. This is benecial for lowering the radiation dose to the patient and in reducing PETCT mismatches, which can arise even in gated studies. The heart and diaphragm were identied through phantom studies as the structures responsible for generating attenuation-correction artefacts in the heart and their motions therefore needed to be considered in transforming the CT. Estimating heart motion was straight-forward, due to its high contrast in PET, however the poor diaphragm contrast meant that additional information was required to track its position. Therefore a diaphragm shape model was constructed using segmented diaphragm surfaces, enabling complete diaphragm surfaces to be produced from incomplete and noisy initial estimates. These complete surfaces, in combination with the estimated heart motions were used to transform the CT. The PET frames were then attenuation-corrected with the transformed CT, reconstructed, aligned and summed, to produce motion-free images. It was found that motion-blurring was reduced through alignment, although benets were marginal in the presence of small respiratory motions. Quantitative accuracy was improved from use of the transformed CT for attenuation-correction (compared with no CT transformation), which was attributed to both the heart and the diaphragm transformations. In comparison to a gated CT, a substantial dose saving and a reduced dependence on gating techniques were achieved, indicating the potential value of the technique in routine clinical procedures.

Download or read book Respiratory Motion Correction in Positron Emission Tomography computerised Tomography Imaging written by Paul Schleyer and published by . This book was released on 2012 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: In dual modality PET-CT imaging, respiratory motion can introduce blurring in PET images and create a spatial mismatch between the PET and CT datasets. Attenuation correction errors can result from this mismatch, which can produce severe artefacts that potentially alter the clinical interpretation of the images. Various approaches of reducing these effects have been developed. Many involve respiratory gated acquisitions which generally require a measure of the respiratory cycle throughout imaging. In this work, a retrospective respiratory gating technique was devel¬oped for both PET and CT which extracts the respiratory cycle from the acquired data itself, removing the requirement for hardware that measures respiration. This data-driven gating method was validated with phantom and patient data, and compared with a hardware based approach of gating. Extensions to the method facilitated the gating of multi-bed position, 3D clinical PET scans. Finally, 60 Ammonia cardiac PET/CT images were used to compare several different ap¬proaches of reducing respiratory induced attenuation correction errors and motion blur. The data-driven respiratory gating method accurately substituted a hardware based approach, and no significant difference was found between images gated with either methods. Gating 11 clinical 3D whole body PET images validated the extended data-driven gating methods and demonstrated successful combination of separate PET bed-positions. All evaluated approaches to reduce respiratory motion artefacts in cardiac imaging demonstrated an average improvement in PET-CT alignment. However, cases were found where alignment worsened and artefacts resulted. Fewer and less severe cases were produced when the 4D attenuation correction data was created from a 3D helical CT and PET derived motion fields. Full motion cor¬rection produced a small effect on average, however in this case no detrimental effects were found.

Download or read book Respiratory and Cardiac Gating in PET An Issue of PET Clinics written by Habib Zaidi and published by Elsevier Health Sciences. This book was released on 2013-01-28 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: The complexity of issues associated with gating studies with PET imaging are mostly unknown among practitioners of the field, which is posing a significant danger to those who undergo such studies. This is particularly true for respiratory gating examination. Topics in this issue include both basic and clinical topics, including views from radiation oncology physicians.

Download or read book Ultra low dose CT based Attenuation Correction for Respiratory Motion Compensation in PET CT Imaging written by Tzu-Cheng Lee and published by . This book was released on 2017 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: Positron emission tomography (PET) is a commonly used imaging tool in the management of patients with lung cancer and is of considerable interest in quantitative imaging of the thorax. Mismatch of PET data with computed tomography (CT) attenuation correction (CTAC) due to respiratory motion is a known source of errors in PET imaging. In theory, this can be corrected by matching individual PET and CT phases which have been generated by respiratory-correlated PET and CT. However, due to the high variability of patient breathing patterns and the nature of the scanning time differences between PET and CT, current respiratory-gated CTAC protocols for the irregular breather may cause additional bias in the PET image values. A ten-fold extension of the CT scanning time duration helps reduce PET imaging bias, but leads to the higher radiation dose to the patient. Lowering the CT source flux level to reduce dose, however, leads to increased noise and bias. Here we test the possibility of using model based iterative reconstruction algorithms (MBIRs) for generating the sparse-view, ultra-low-dose (i.e. an order lower than current low-dose protocols) CTAC images for both phantom and patient PET data. We also propose a new variance estimation model, which considers statistical changes caused by the non-positivity correction process, for the MBIR algorithms. The model based iterative CT reconstruction approach does generate more accurate CTAC map compared to current approaches. However, since iterative reconstruction algorithms typically assume a normal distribution of the attenuation data, we tested if the assumption is still valid in the ultra-low-dose regime. The simulation and empirical ultra-low-dose CT studies showed a skewed post-log likelihood distribution in certain ranges. The information delineates the estimation limits of model based iterative reconstruction approach on the ultra-low-dose CT imaging, and potentially helps guide scanning protocols customized for a lowest-reasonable radiation dose.

Download or read book Cardiac PET and PET CT Imaging written by Marcello F. Di Carli and published by Springer Science & Business Media. This book was released on 2007-12-05 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the most up-to-date information on the practice of cardiac PET and hybrid PET/CT. Each chapter takes a step-by-step approach, from basic principles of instrumentation, imaging, and protocols to advanced discussions of current and future clinical applications. Coverage also includes a perspective on other emerging imaging modalities, such as MRI, and the relative role of each. In addition, the volume details the technical aspects of cardiac PET and PET/CT imaging. A library of original cases completes the text by illustrating interpretation and technical challenges in cardiac PET and hybrid PET/CT.

Download or read book PET CT and Artefacts written by Katalin Nemeth and published by . This book was released on 2014 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: Positron Emission Tomography (PET) is a very commonly used molecular and functional imaging method in the field of oncology for diagnosis, staging, follow-up and radiotherapy planning. Computed Tomography (CT) is used for attenuation correction and adding anatomical information. In this thesis, the basics of PET-CT imaging were explained, and possible artefacts were described and classified as PET-based, CT-based and attenuation correction based artefacts. Respiratory artefacts were discussed in the main part of the thesis. The underlying mechanisms (CT can be performed in a few seconds with respiratory hold technique, PET imaging is performed in 6-30 minutes normally with free breathing) were described. The literature research gave a review over respiratory artefacts and state of the art techniques to avoid or at least reduce them. In general, there are three different approaches: pre-reconstruction methods, motion corrections during reconstruction and post-reconstruction correction techniques. There are numerous technical devices used (e.g. impedance based, temperature based, video based, spirometry based) in the clinical practice, and other authors suggest software based solutions (e.g. gated + algorithm). These different possibilities were described and their advantages and disadvantages were shown. Especially for software based solutions there were only limited clinical data, but for most of the methods described here were existing clinical data (at least preliminary data) showing that reducing respiratory artefacts could result in higher rates of lesion detection (higher sensitivity of PET-CT) without a loss of specificity.*****Positron Emission Tomography (PET) is a very commonly used molecular and functional imaging method in the field of oncology for diagnosis, staging, follow-up and radiotherapy planning. Computed Tomography (CT) is used for attenuation correction and adding anatomical information. In this thesis, the basics of PET-CT imaging were explained, and possible artefacts were described and classified as PET-based, CT-based and attenuation correction based artefacts. Respiratory artefacts were discussed in the main part of the thesis. The underlying mechanisms (CT can be performed in a few seconds with respiratory hold technique, PET imaging is performed in 6-30 minutes normally with free breathing) were described. The literature research gave a review over respiratory artefacts and state of the art techniques to avoid or at least reduce them. In general, there are three different approaches: pre-reconstruction methods, motion corrections during reconstruction and post-reconstruction correction techniques. There are numerous technical devices used (e.g. impedance based, temperature based, video based, spirometry based) in the clinical practice, and other authors suggest software based solutions (e.g. gated + algorithm). These different possibilities were described and their advantages and disadvantages were shown. Especially for software based solutions there were only limited clinical data, but for most of the methods described here were existing clinical data (at least preliminary data) showing that reducing respiratory artefacts could result in higher rates of lesion detection (higher sensitivity of PET-CT) without a loss of specificity.

Download or read book PET CT Imaging written by Kanhaiyalal Agrawal and published by Springer Nature. This book was released on 2021-12-02 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this book is to provide concise information and quick reference on the basics and practice of PET/CT for beginners. The chapters are written by Nuclear Medicine experts from different countries with enormous experience in PET/CT practice. Starting with the basics of PET/CT describing physics and the use of radiopharmaceuticals in PET/CT, the book explores the principle of PET/CT in radiotherapy planning. The last five chapters explore normal variation, pitfalls and artefacts commonly seen with various routinely used PET radiotracers. The text is enriched by tables and highlighted clinical cases for better understanding. This book will be of interest mostly to nuclear medicine physicians and radiologists, but it may be appealing also to a wider medical community including oncologists and radiotherapists.

Download or read book Quantification of Respiratory Motion in PET CT and Its Significance in Radiation Therapy written by Chandrani Chakraborty and published by . This book was released on 2008 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Respiratory Motion compensation in 82Rb Cardiac PET CT written by Amir Pourmoghaddas and published by . This book was released on 2010 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Respiratory Motion Modeling for Use in Diagnostic Imaging and Radiation Therapy written by Hadi Fayad and published by . This book was released on 2011 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the most important parameters reducing the sensitivity and specificity in the thoracic and abdominal areas is respiratory motion and associated deformations which represent today an important challenge in medical imaging. In addition, respiratory motion reduces accuracy in image fusion from combined positron emission tomography computed tomography (PET/CT) systems. Solutions presented to date include respiratory synchronized PET and CT acquisitions. However, differences between acquired 4D PET and corresponding CT image series have been reported due to differences in respiration conditions during PET and CT acquisitions. In addition, the radiation dose burden resulting from a 4D CT acquisition may not be justifiable for every patient. The first objective of this thesis was to generate dynamic CT images from one reference CT image; based on deformation matrices obtained from the elastic registration of 4D non attenuation corrected PET images. Such an approach eliminates, on one hand the need for the acquisition of dynamic CT, while at the same time ensuring the good matching between CT and PET images. The second objective was to develop and evaluate methods of building patient specific respiratory motion models and at as a second step more developed generic respiratory motion models. These models relate the internal motion to the parameters of an external surrogate signal (PET respiratory signal or patient's surface) that can be acquired during data acquisition and treatment delivery. Finally, the two developed models were validated and used in the PET respiratory motion and attenuation correction and in radiation therapy applications.

Download or read book Spet CT Atlas on Quality Control and Image Artefacts written by International Atomic Energy Agency and published by . This book was released on 2019-12-31 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: SPECT/CT Atlas of Quality Control and Image Artefacts

Download or read book Comprehensive Biomedical Physics written by and published by Newnes. This book was released on 2014-07-25 with total page 4052 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Biomedical Physics, Ten Volume Set is a new reference work that provides the first point of entry to the literature for all scientists interested in biomedical physics. It is of particularly use for graduate and postgraduate students in the areas of medical biophysics. This Work is indispensable to all serious readers in this interdisciplinary area where physics is applied in medicine and biology. Written by leading scientists who have evaluated and summarized the most important methods, principles, technologies and data within the field, Comprehensive Biomedical Physics is a vital addition to the reference libraries of those working within the areas of medical imaging, radiation sources, detectors, biology, safety and therapy, physiology, and pharmacology as well as in the treatment of different clinical conditions and bioinformatics. This Work will be valuable to students working in all aspect of medical biophysics, including medical imaging and biomedical radiation science and therapy, physiology, pharmacology and treatment of clinical conditions and bioinformatics. The most comprehensive work on biomedical physics ever published Covers one of the fastest growing areas in the physical sciences, including interdisciplinary areas ranging from advanced nuclear physics and quantum mechanics through mathematics to molecular biology and medicine Contains 1800 illustrations, all in full color

Download or read book The EACVI Textbook of Cardiovascular Magnetic Resonance written by Victor Ferrari and published by Oxford University Press. This book was released on 2018-09-20 with total page 1024 pages. Available in PDF, EPUB and Kindle. Book excerpt: This highly comprehensive and informed textbook has been prepared by the Cardiovascular Magnetic Resonance section of the European Society of Cardiology association on imaging, the EACVI. The EACVI Textbook of Cardiovascular Magnetic Resonance is the authority on the subject. The textbook is aligned with ESC Core Curriculum and EACVI Core Syllabus for CMR. It is a practical resource and provides a disease orientated outlook on the subject. Structured with thirteen clear and detailed sections, ranging from Physics to Methodology, and featuring specific sections on ischemic heart disease, myocardial disease, pericardial disease, and congenital heart disease and adult congenital heart disease, The EACVI Textbook of Cardiovascular Magnetic Resonance provides extensive knowledge across the entire subject area in CMR. Beautifully illustrated and physical principles enriched with schematic animations, the textbook is advanced further with key video content based on clinical cases. Written by leading experts in the field from across the world, the textbook aims to summarise the existing research and clinical evidence for the various CMR indications and provide an invaluable resource for cardiologists and radiologists across the board. The textbook is ideal for cardiologists and radiologists new to the field of Cardiovascular Magnetic Resonance, those preparing for ESC certification in CMR, and those established in the field wishing to gain a deep understanding of CMR. Online access to the digital version is included with purchase of the print book, with accompanying videos referenced within the text available on Oxford Medicine Online.

Download or read book Hybrid Cardiac Imaging written by Stephan G. Nekolla and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This clinically oriented book provides an up-to-date review on the various hybrid imaging modalities that may be employed for the purpose of cardiac imaging. After discussion of generic aspects of hybrid imaging, SPECT/CT, PET/CT, and PET/MRI are each considered in depth. In addition, information is provided on upcoming technologies, such as dedicated so-called fast cardiac cameras (CZT detector technology) and novel probes and radiotracers. A wide variety of topics are addressed, including important technological aspects, possible applications, imaging protocols, peculiarities of the available modalities, radiation exposure, and dose reduction. Last but not least, an estimation of the cost efficiency of dedicated and hybrid imaging devices in cardiology is provided and possible scenarios with respect to health care economics are envisioned. Hybrid Cardiac Imaging will be of particular value for nuclear medicine specialists, cardiologists, and radiologists and will also be of interest to medical physicists, medical technicians, and cardiothoracic surgeons. .

Download or read book PET CT Atlas on Quality Control and Image Artefacts written by International Atomic Energy Agency and published by . This book was released on 2014 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: Positron emission tomography/computed tomography (PET/CT), as any other imaging modality, is acceptable for routine clinical and research applications only if technical pitfalls can be avoided. Artefacts from incorrect or sub-optimal acquisition procedures should be recognized and, if possible, corrected retrospectively and the resulting image information interpreted correctly, which entails an appreciation of variants of the represented image information. This publication provides guidance on the physics and technical aspects behind PET and PET/CT image distortions. Cases are presented to provide nuclear medicine and radiology professionals with an assortment of examples of possible image distortions and errors in order to support a correct image interpretation. Nearly 70 typical PET and PET/CT cases, comprising image sets and cases, have been collected in this volume, all catalogued and augmented with explanations as to the causes of, and solutions to, each individual image problem. The atlas will prove useful to physicists, physicians, technologists, and service engineers in the clinical field.

Download or read book Oncologic and Cardiologic PET CT Diagnosis written by Wolfgang Mohnike and published by Springer Science & Business Media. This book was released on 2008-07-24 with total page 741 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on the experience gained by PET/CT experts with more than 10,000 patients, this manual impressively demonstrates the advantages of combined PET/CT. It also refers to publications from Europe, the USA and Asia as well as numerous studies.

Download or read book 99mTc Sestamibi written by Jan Bucerius and published by Springer Science & Business Media. This book was released on 2011-09-22 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: 99mTc-sestamibi is a single-photon emission computed tomography (SPECT) radiotracer that is widely used for the imaging of myocardial perfusion, as well as a variety of malignant and benign diseases. 99mTc-Sestamibi – Clinical Applications provides a detailed and informative overview of almost all the oncologic and non-oncologic applications of 99mTc-sestamibi SPECT, including several relatively rare indications. Different disease-related protocols for 99mTc-sestamibi SPECT are presented, and for each disease a comprehensive summary of the relevant pathology and epidemiology is provided. Throughout, there is a strong emphasis on the practical aspects of use of this popular tracer, including instructions for the preparation of several commercially available tracer kits. Clinical practitioners will find this book to be an invaluable guide to the application and benefits of 99mTc-sestamibi SPECT in both the inpatient and the outpatient setting.