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FIGURES OF MERIT FOR COMPARING reconstruction algorithmS WITH A VOLUME-IMAGING PET SCANNER

PHYSICS IN MEDICINE AND BIOLOGY 1994年第3期39卷 631-642页

作者： KINAHAN, PE KARP, JS Department of Radiology University of Pennsylvania 110 Donner Building 3400 Spruce Street Philadelphia PA 19104 USA.

For volume-imaging PET scanners, no septa are used to maximize the sensitivity by collecting events oblique to the scanner axis. We answer two questions: (i) how does the performance of an image reconstruction algorithm for a volume-imaging PET scanner depend on its general dimensions? and (ii) at what point is a three-dimensional (3D) reconstruction algorithm needed for a volume-imaging scanner, as the axial extent is increased? A 3D reconstruction algorithm will accurately incorporate the oblique events in a reconstruction of the original source distribution. From simulations of an existing volume PET scanner with a maximum axial acceptance angle (+/-alpha) of alpha = 9 degrees, however, we show that the single-slice rebinning algorithm is a good compromise between sensitivity, speed, and accuracy when compared to standard two-dimensional reconstruction (alpha = 1 degrees), and a 3D reconstruction with alpha = 9 degrees. We also show with simulations that a new scanner with alpha = 27 degrees requires 3D, reconstruction in order to achieve maximum sensitivity without unacceptable losses in accuracy. Measurements of scanner performance are based on a series of figures of merit that characterize image quality and quantitative accuracy measured from a set of simulated test phantoms.

关键词： Positron Emission Tomography Systems Scanner acceptance angle peak response Quality factor Magneto electrical resistivity imaging technique three-dimensional displays Figure Adrenergic alpha-Antagonists simulating reconstruction algorithm

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Relevance of statistically significant differences between reconstruction algorithms

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IEEE TRANSACTIONS ON IMAGE PROCESSING 1996年第3期5卷 554-556页

作者： Matej, S Furuie, SS Herman, GT Medical Image Processing Group Department ofRadiology University of Pennsylvania PA USA

When comparing reconstruction algorithms, differences in figures of performance merit that are too small to be of any practical relevance may still be statistically significant. We formalize the notion of ''relevance'' and propose an evaluation methodology in which statistical significance is retained for relevant improvements, but not for irrelevant ones.

关键词： reconstruction algorithm Statistical Significance Evaluation Methodology

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ISOTOPE COMPUTED-TOMOGRAPHY USING CONE-BEAM GEOMETRY - A COMPARISON OF 2 reconstruction algorithmS

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PHYSICS IN MEDICINE AND BIOLOGY 1987年第10期32卷 1221-1235页

作者： HORSMAN, A SUTCLIFFE, J BURKINSHAW, L WILD, P SKILLING, J WEBB, S UNIV LEEDS DEPT MED PHYS LEEDS LS1 3EX W YORKSHIRE ENGLAND UNIV CAMBRIDGE DEPT APPL MATH & THEORET PHYS CAMBRIDGE CB3 9EW ENGLAND ROYAL MARSDEN HOSP JOINT DEPT PHYS SUTTON SM2 5PT SURREY ENGLAND INST CANC RES JOINT DEPT PHYS SUTTON SM2 5PT ENGLAND

A CT scanner has been constructed specifically to determine the three-dimensional distribution of bone mineral in the medullary cavities of the radius, ulna and femur. A source of x-rays (153Gd) and a multiwire proportional counter (MWPC) are mounted at opposite ends of a diameter of an annular mounting. The limb is placed on the axis of rotation of the annulus and a series of two-dimensional transmission projections are obtained at equal angular spacings over ***.. The distribution of bone mineral is reconstructed from the projections either by the method of maximum entropy (ME) or by convolution and back projection (CBP). These two methods have been evaluated by reconstructing a single slice of a phantom, representing the forearm, from projections simulated by computer. With a clinically acceptable exposure time, the mean medullary densities of the ulna and radius were determined with systematic errors of less than 3.5% (ME) and 11% (CBP), although for the latter method of reconstruction the systematic error was reduced to less than 2% by increasing the number of views. The mean medullary densities of the ulna and radius were determined with precisions better than 2.5% (ME) and 3.5% (CBP).

关键词： Bone minerals Radius PROJECTION CREB-Binding Protein Systematic errors Medulla Oblongata Maximum entropy Ulna reconstruction algorithm Convolution X-Ray Computed Tomography Scanners rotating shafts Radius and Ulna Radius isotopes

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Evaluation of 3D reconstruction algorithms for a small animal PET camera

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IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1997年第3期44卷 1303-1308页

作者： Johnson, CA Seidel, J Carson, RE Gandler, WR Sofer, A Green, MV DaubeWitherspoon, ME NIH DEPT NUCL MEDCTR CLINBETHESDAMD 20892 NIH PET DEPTCTR CLINBETHESDAMD 20892 GEORGE MASON UNIV FAIRFAXVA 22030

The use of paired, opposing position-sensitive phototube scintillation cameras (SCs) operating in coincidence for small animal imaging with positron emitters is currently under study. Because of the low sensitivity of the system even in 3D mode and the need to produce images with high resolution, it was postulated that a 3D expectation maximization (EM) reconstruction algorithm might be well suited for this application. We investigated six reconstruction algorithms for the 3D SC PET camera: 2D filtered back-projection (FBP), 3D reprojection (3DRP), 2D EM, 3D EM, 2D ordered subset EM (OSEM), and 3D OSEM. Noise was assessed for all slices by the coefficient of variation in a simulated uniform cylinder. Resolution was assessed from a simulation of 15 point sources in the warm background of the uniform cylinder. At comparable noise levels, the resolution achieved with EM and OSEM (0.9-mm to 1.2-mm) is significantly better than that obtained with FBP or 3DRP (1.5-mm to 2.0-mm.) Images of a rat skull labeled with F-18-fluoride suggest that 3D EM and 3D OSEM can improve image quality of a small animal PET camera.

关键词： Point sources Cameras Three Dimensions low sensitivity Image quality three-dimensional displays Noise levels COEFFICIENT OF VARIATION Animals reconstruction algorithm Coincidence

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An Efficient algorithm for reconstruction of Discrete Sets from Horizontal Projections with Absorption 1

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3rd International Conference on Information Computing and Applications (ICICA 2012)

作者： Chen Junyu Gao Aili Zhang Chuanlin Jinan Univ Coll Informat Sci & Technol Guangzhou 510632 Guangdong Peoples R China

ISBN: (数字)9783642340383

ISBN: (纸本)9783642340376

This paper considered that two projections along the left and right horizontal directions uniquely determine a binary matrix when the absorbed coefficient is special. For the weakness of computational complexity of projection difference, an improved algorithm is proposed to reconstruct binary matrices along the diagonal projections based on determining conditions of sequence consistency. Furthermore, comparing with the existing algorithm, it's more efficient to search solutions.

关键词： Discrete tomography Discrete model with absorption reconstruction algorithm

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Electromagnetic Model and Image reconstruction algorithms Based on EIT System

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Transactions of Tianjin University 2006年第6期12卷 420-424页

作者：曹章王化祥 School of Electrical Engineering and Automation Tianjin University

An intuitive 2D model of circular electrical impedance tomography （EIT） sensor with small size electrodes is established based on the theory of analytic functions. The validation of the model is proved using the result from the solution of Laplace equation. Suggestions on to electrode optimization and explanation to the ill-condition property of the sensitivity matrix are provided based on the model, which takes electrode distance into account and can be generalized to the sensor with any simple connected region through a conformal transformation. Image reconstruction algorithms based on the model are implemented to show feasibility of the model using experimental data collected from the EIT system developed in Tianjin University. In the simulation with a human chestlike configuration, electrical conductivity distributions are reconstructed using equi-potential backprojection （EBP） and Tikhonov regularization （TR） based on a conformal transformation of the model. The algorithms based on the model are suitable for online image reconstruction and the reconstructed results are aood both in size and position.

关键词： electrical impedance tomography electromagnetic model conformal transformation reconstruction algorithm

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An algorithm for the reconstruction of discrete sets from two projections in presence of absorption

An algorithm for the reconstruction of discrete sets from tw...

引用

9th International Workshop on Combinatorial Image Analysis

作者： Barcucci, E Frosini, A Rinaldi, S Univ Florence Dipartimento Sistemi & Informat I-50134 Florence Italy Univ Siena Dipartimento Sci Matemat & Informat Roberto Magar I-53100 Siena Italy

In this paper we consider the problem of reconstructing a binary matrix from absorbed projections, as introduced in [Kuba and Nivat, Linear Algebra Appl. 3 39 (2001) 171-194]. In particular we prove that two left and right horizontal absorbed projections along a single direction uniquely determine a row of a binary matrix for a specific absorption coefficient. Moreover, we give a linear time algorithm which reconstructs such a row and we analyze its performances by determining the worst case complexity. Finally, we study the same problems in the presence of different absorption coefficients. (c) 2005 Elsevier B.V. All rights reserved.

关键词： discrete tomography discrete model with absorption reconstruction algorithm

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Multiple-fiber reconstruction algorithms for diffusion MRI

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WHITE MATTER IN COGNITIVE NEUROSCIENCE: ADVANCES IN DIFFUSION TENSOR IMAGING AND ITS APPLICATIONS 2005年第1期1064卷 113-+页

作者： Alexander, DC UCL Dept Comp Sci London WC1E 6BT England

This chapter reviews multiple-fiber reconstruction algorithms for diffusion magnetic resonance imaging (MRI) and provides some initial comparative results for two such algorithms, q-ball imaging and PASMRI, on data from a typical clinical diffusion MRI acquisition. The chapter highlights the problems with standard approaches, such as diffusion-tensor MRI, to motivate a recent set of alternative approaches. The review concentrates on the software implementation of the new techniques. Results of the preliminary comparison show that PASMRI recovers the principal directions of simple test functions more consistently than q-ball imaging and produces qualitatively better results on the test data set. Further simulations suggest that a moderate increase in data quality allows q-ball, which is much faster to run, to recover directions with consistency comparable to that of PASMRI on the test data.

关键词： diffusion MRI fiber reconstruction algorithm white matter imaging q-ball PASMRI

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Adaptive reconstruction based on Romp algorithm

Adaptive reconstruction based on Romp algorithm

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2nd International Conference on Materials and Products Manufacturing Technology (ICMPMT 2012)

作者： Xu, Xiaohui Chen, Dongfang Wuhan Univ Sci & Technol Wuhan Hubei Province Peoples R China

ISBN: (纸本)9783037855447

Romp algorithm can reconstruct the signal fast and accurate as long as the signal satisfy Restricted Isometry Property. However, the number of iterations will affect the quality of the image reconstruction directly while the sparsity of the signal is unknown. A new solution will be put forward in this paper which can get the reasonable iteration times of the ROMP algorithm base on some knowledge of each iteration process, Experiments show that this solution can get good quality reconstruction for the image of different features.

关键词： Compressed sensing reconstruction algorithm Matching pursuit

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reconstruction of in-line hologram by using iterative algorithm

Reconstruction of in-line hologram by using iterative algori...

引用

Conference on Optical Measurement Systems for Industrial Inspection IV

作者： Zhang, Y Capital Normal Univ Dept Phys Beijing 100037 Peoples R China

ISBN: (纸本)0819458562

In-line holography is a simple approach for high resolution imaging. It has been extensively investigated due to it can effectively utilize the space-bandwidth of the digital recording instrument, such as CCD or CMOS. However, since the fact that the reference wave and the object wave are overlapped during the hologram was recorded, the reconstructed image is blurred by the ghost image. This shortcoming limits the applications of the in-line holography. Therefore, an effective reconstruction algorithm is important for generalizing the application of the in-line holography. In this presentation, some approaches based on the iterative phase retrieval algorithms are reported for in-line holograms reconstruction. Firstly, the YG algorithm and the GS algorithm are used to reconstruct pure absorption object from their in-line holograms, respectively. The differences between these two algorithms on in-line hologram reconstruction are analyzed. Then the GS algorithm is extended to reconstruct whole optical field form double or multiple holograms. At last, a new approach for reconstructing object from a hologram series is presented. Experimental results show that all these methods can reconstruct original object well.

关键词： digital holography in-line holography reconstruction algorithm iterative algorithm

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