Development and Implementation of Fully 3D Statistical Image Reconstruction Algorithms for Helical CT and Half-ring PET Insert System

Development and Implementation of Fully 3D Statistical Image Reconstruction Algorithms for Helical CT and Half-ring PET Insert System PDF Author: Daniel Brian Keesing
Publisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 159

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Book Description
X-ray computed tomography (CT) and positron emission tomography (PET) have become widely used imaging modalities for screening, diagnosis, and image-guided treatment planning. Along with the increased clinical use are increased demands for high image quality with reduced ionizing radiation dose to the patient. Despite their significantly high computational cost, statistical iterative reconstruction algorithms are known to reconstruct high-quality images from noisy tomographic datasets. The overall goal of this work is to design statistical reconstruction software for clinical x-ray CT scanners, and for a novel PET system that utilizes high-resolution detectors within the field of view of a whole-body PET scanner. The complex choices involved in the development and implementation of image reconstruction algorithms are fundamentally linked to the ways in which the data is acquired, and they require detailed knowledge of the various sources of signal degradation. Both of the imaging modalities investigated in this work have their own set of challenges. However, by utilizing an underlying statistical model for the measured data, we are able to use a common framework for this class of tomographic problems. We first present the details of a new fully 3D regularized statistical reconstruction algorithm for multislice helical CT. To reduce the computation time, the algorithm was carefully parallelized by identifying and taking advantage of the specific symmetry found in helical CT. Some basic image quality measures were evaluated using measured phantom and clinical datasets, and they indicate that our algorithm achieves comparable or superior performance over the fast analytical methods considered in this work. Next, we present our fully 3D reconstruction efforts for a high-resolution half-ring PET insert. We found that this unusual geometry requires extensive redevelopment of existing reconstruction methods in PET. We redesigned the major components of the data modeling process and incorporated them into our reconstruction algorithms. The algorithms were tested using simulated Monte Carlo data and phantom data acquired by a PET insert prototype system. Overall, we have developed new, computationally efficient methods to perform fully 3D statistical reconstructions on clinically-sized datasets.

Development and Implementation of Fully 3D Statistical Image Reconstruction Algorithms for Helical CT and Half-ring PET Insert System

Development and Implementation of Fully 3D Statistical Image Reconstruction Algorithms for Helical CT and Half-ring PET Insert System PDF Author: Daniel Brian Keesing
Publisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 159

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Book Description
X-ray computed tomography (CT) and positron emission tomography (PET) have become widely used imaging modalities for screening, diagnosis, and image-guided treatment planning. Along with the increased clinical use are increased demands for high image quality with reduced ionizing radiation dose to the patient. Despite their significantly high computational cost, statistical iterative reconstruction algorithms are known to reconstruct high-quality images from noisy tomographic datasets. The overall goal of this work is to design statistical reconstruction software for clinical x-ray CT scanners, and for a novel PET system that utilizes high-resolution detectors within the field of view of a whole-body PET scanner. The complex choices involved in the development and implementation of image reconstruction algorithms are fundamentally linked to the ways in which the data is acquired, and they require detailed knowledge of the various sources of signal degradation. Both of the imaging modalities investigated in this work have their own set of challenges. However, by utilizing an underlying statistical model for the measured data, we are able to use a common framework for this class of tomographic problems. We first present the details of a new fully 3D regularized statistical reconstruction algorithm for multislice helical CT. To reduce the computation time, the algorithm was carefully parallelized by identifying and taking advantage of the specific symmetry found in helical CT. Some basic image quality measures were evaluated using measured phantom and clinical datasets, and they indicate that our algorithm achieves comparable or superior performance over the fast analytical methods considered in this work. Next, we present our fully 3D reconstruction efforts for a high-resolution half-ring PET insert. We found that this unusual geometry requires extensive redevelopment of existing reconstruction methods in PET. We redesigned the major components of the data modeling process and incorporated them into our reconstruction algorithms. The algorithms were tested using simulated Monte Carlo data and phantom data acquired by a PET insert prototype system. Overall, we have developed new, computationally efficient methods to perform fully 3D statistical reconstructions on clinically-sized datasets.

3D Image Reconstruction for CT and PET

3D Image Reconstruction for CT and PET PDF Author: Daniele Panetta
Publisher: CRC Press
ISBN: 100017588X
Category : Medical
Languages : en
Pages : 97

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Book Description
This is a practical guide to tomographic image reconstruction with projection data, with strong focus on Computed Tomography (CT) and Positron Emission Tomography (PET). Classic methods such as FBP, ART, SIRT, MLEM and OSEM are presented with modern and compact notation, with the main goal of guiding the reader from the comprehension of the mathematical background through a fast-route to real practice and computer implementation of the algorithms. Accompanied by example data sets, real ready-to-run Python toolsets and scripts and an overview the latest research in the field, this guide will be invaluable for graduate students and early-career researchers and scientists in medical physics and biomedical engineering who are beginners in the field of image reconstruction. A top-down guide from theory to practical implementation of PET and CT reconstruction methods, without sacrificing the rigor of mathematical background Accompanied by Python source code snippets, suggested exercises, and supplementary ready-to-run examples for readers to download from the CRC Press website Ideal for those willing to move their first steps on the real practice of image reconstruction, with modern scientific programming language and toolsets Daniele Panetta is a researcher at the Institute of Clinical Physiology of the Italian National Research Council (CNR-IFC) in Pisa. He earned his MSc degree in Physics in 2004 and specialisation diploma in Health Physics in 2008, both at the University of Pisa. From 2005 to 2007, he worked at the Department of Physics "E. Fermi" of the University of Pisa in the field of tomographic image reconstruction for small animal imaging micro-CT instrumentation. His current research at CNR-IFC has as its goal the identification of novel PET/CT imaging biomarkers for cardiovascular and metabolic diseases. In the field micro-CT imaging, his interests cover applications of three-dimensional morphometry of biosamples and scaffolds for regenerative medicine. He acts as reviewer for scientific journals in the field of Medical Imaging: Physics in Medicine and Biology, Medical Physics, Physica Medica, and others. Since 2012, he is adjunct professor in Medical Physics at the University of Pisa. Niccolò Camarlinghi is a researcher at the University of Pisa. He obtained his MSc in Physics in 2007 and his PhD in Applied Physics in 2012. He has been working in the field of Medical Physics since 2008 and his main research fields are medical image analysis and image reconstruction. He is involved in the development of clinical, pre-clinical PET and hadron therapy monitoring scanners. At the time of writing this book he was a lecturer at University of Pisa, teaching courses of life-sciences and medical physics laboratory. He regularly acts as a referee for the following journals: Medical Physics, Physics in Medicine and Biology, Transactions on Medical Imaging, Computers in Biology and Medicine, Physica Medica, EURASIP Journal on Image and Video Processing, Journal of Biomedical and Health Informatics.

The Theory and Practice of 3D PET

The Theory and Practice of 3D PET PDF Author: B. Bendriem
Publisher: Springer Science & Business Media
ISBN: 9401734755
Category : Medical
Languages : en
Pages : 180

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Book Description
The application of 3D methodology has recently been receiving increasing attention at many PET centres, and this monograph is an attempt to provide a state-of-the-art review of this methodology, covering 3D reconstruction methods, quantitative procedures, current tomography performance, and clinical and research applications. No such review has been available until now to assist PET researchers in understanding and implementing 3D methodology, and in evaluating the performance of the available imaging technology. In all the chapters, the subject matter is treated in sufficient depth to appeal equally to the physicist or engineer who wishes to establish the methodology, and to PET investigators with experience in 2D PET who wish to familiarize themselves with the concepts and advantages of 3D, and to be made aware of the pitfalls.

Statistical Modeling and Path-based Iterative Reconstruction for X-ray Computed Tomography

Statistical Modeling and Path-based Iterative Reconstruction for X-ray Computed Tomography PDF Author: Meng Wu
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
X-ray computed tomography (CT) and tomosynthesis systems have proven to be indispensable components in medical diagnosis and treatment. My research is to develop advanced image reconstruction and processing algorithms for the CT and tomosynthesis systems. Streak artifacts caused by metal objects such as dental fillings, surgical instruments, and orthopedic hardware may obscure important diagnostic information in X-ray computed tomography (CT) images. To improve the image quality, we proposed to complete the missing kilovoltage (kV) projection data with selectively acquired megavoltage (MV) data that do not suffer from photon starvation. We developed two statistical image reconstruction methods, dual-energy penalized weighted least squares and polychromatic maximum likelihood, for combining kV and selective MV data. Cramer-Rao Lower Bound for Compound Poisson was studied to revise the statistical model and minimize radiation dose. Numerical simulations and phantom studies have shown that the combined kV/MV imaging systems enable a better delineation of structures of interest in CT images for patients with metal objects. The x-ray tube on the CT system produces a wide x-ray spectrum. Polychromatic statistical CT reconstruction is desired for more accurate quantitative measurement of the chemical composition and density of the tissue. Polychromatic statistical reconstruction algorithms usually have very high computational demands due to complicated optimization frameworks and the large number of spectrum bins. We proposed a spectrum information compression method and a new optimization framework to significantly reduce the computational cost in reconstructions. The new algorithm applies to multi-material beam hardening correction, adaptive exposure control, and spectral imaging. Model-based iterative reconstruction (MBIR) techniques have demonstrated many advantages in X-ray CT image reconstruction. The MBIR approach is often modeled as a convex optimization problem including a data fitting function and a penalty function. The tuning parameter value that regulates the strength of the penalty function is critical for achieving good reconstruction results but is difficult to choose. We have developed two path seeking algorithms that are capable of generating a path of MBIR images with different strengths of the penalty function. The errors of the proposed path seeking algorithms are reasonably small throughout the entire reconstruction path. With the efficient path seeking algorithm, we suggested a path-based iterative reconstruction (PBIR) to obtain complete information from the scanned data and reconstruction model. Additionally, we have developed a convolution-based blur-and-add model for digital tomosynthesis systems that can be used in efficient system analysis, task-dependent optimization, and filter design. We also proposed a computationally practical algorithm to simulate and subtract out-of-plane artifacts in tomosynthesis images using patient-specific prior CT volumes.

Statistical Image Reconstruction Algorithms Using Paraboloidal Surrogates for PET Transmission Scans

Statistical Image Reconstruction Algorithms Using Paraboloidal Surrogates for PET Transmission Scans PDF Author: Hakan Erdoğan
Publisher:
ISBN:
Category :
Languages : en
Pages : 380

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Programs for Evaluation of 3D PET Reconstruction Algorithms

Programs for Evaluation of 3D PET Reconstruction Algorithms PDF Author: S. S. Furuie
Publisher:
ISBN:
Category :
Languages : en
Pages : 112

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Book Description


Statistical Reconstruction Algorithms for Polyenergetic X-ray Computed Tomography

Statistical Reconstruction Algorithms for Polyenergetic X-ray Computed Tomography PDF Author: Idris A. Elbakri
Publisher:
ISBN:
Category :
Languages : en
Pages : 358

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Book Description


Convergent Algorithms for Statistical Image Reconstruction in Emission Tomography

Convergent Algorithms for Statistical Image Reconstruction in Emission Tomography PDF Author: Sangtae Ahn
Publisher:
ISBN:
Category :
Languages : en
Pages : 378

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Residual Correction Algorithms for Statistical Image Reconstruction in Positron Emission Tomography

Residual Correction Algorithms for Statistical Image Reconstruction in Positron Emission Tomography PDF Author: Lin Fu
Publisher:
ISBN: 9781124025315
Category :
Languages : en
Pages :

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Book Description
Positron emission tomography (PET) is a radionuclide imaging modality that plays important roles in visualizing, targeting, and quantifying functional processes in vivo. High-resolution and quantitative PET images are reconstructed by solving large-scale inverse problems with iterative methods that incorporate accurate physics and noise modeling of the imaging process. The computation demands of PET image reconstruction are rapidly increasing as higher-resolution detectors, larger imaging field-of-view, and dynamic or adaptive data acquisition modes are being adopted by modern PET scanners. The trend of the increase in the computation demands is even faster than Moore's law that describes the exponential growth in the number of transistors placed on an integrated circuit. In this project a residual correction mechanism is introduced to PET image reconstruction to create computationally efficient yet accurate tomographic reconstruction algorithms. By using residual correction, reconstruction methods are able to adopt a more simplified physical model for fast computation while retaining the accuracy of the final solution. Residual correction can accelerate existing image reconstruction packages. It allows iterative reconstruction with more accurate physical models which are currently impractical due to the high computation cost. Two illustrative applications of the residual correction approach are provided. One is image reconstruction with an object-dependent Monte Carlo based physics model. The other is image reconstruction using an ultra fast GPU-accelerated simplified geometric model.

3D Image Reconstruction for PET by Multi-slice Rebinning and Axial Filtering

3D Image Reconstruction for PET by Multi-slice Rebinning and Axial Filtering PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 9

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Book Description
Two different approaches are used at present to reconstruct from 3D coincidence data in PET. We refer to these approaches as the single-slice rebinning approach and the fully-3D approach. The single-slice rebinning approach involves geometrical approximations, but it requires the least possible amount of computation. Fully-3D reconstruction algorithms, both iterative and non-iterative, do not make such approximations, but require much more computation. Multi-slice rebinning with axial filtering is a new approach which attempts to achieve the geometrical accuracy of the fully-3D approach with the simplicity and modest amount of computation of the single-slice rebinning approach. The first step (multi-slice rebinning) involves rebinning of coincidence lines into a stack of 2D sinograms, where multiple sinograms are incremented for each oblique coincidence line. This operation is followed by an axial filtering operation, either before or after slice-by-slice reconstruction, to reduce the blurring in the axial direction. Tests with simulated and experimental data indicate that the new method has better geometrical accuracy than single-slice rebinning, at the cost of only a modest increase in computation. 11 refs.