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Sparse reconstruction for fluorescence molecular tomography via a fast iterative algorithm

Journal of Innovative Optical Health Sciences 2014年第3期7卷 50-58页

作者： Jingjing Yu Jingxing Cheng Yuqing Hou Xiaowei He School of Physics and Information Technology Shaanai Normal University Xian 710062P.R.China School of Information Sciences and Technology Northwest University Xi'an 710069P.R.China

Fluorescence molecular tomography(FMT)is a fast-developing optical imaging modalitythat has great potential in early diagnosis of disease and drugs ***,recon-struction algorithms have to address a highly ill-posed problem to fulfll 3D reconstruction *** this contribution,we propose an efficient iterative algorithm to solve the large-scalereconstruction problem,in which the sparsity of fluorescent targets is taken as useful a prioriinformation in designing the reconstruction *** the implementation,a fast sparseapproximation scheme combined with a stage-wise learning strategy enable the algorithm to dealwith the ill-posed inverse problem at reduced computational *** validate the proposed fastiterative method with numerical simulation on a digital mouse *** results demonstrate that our method is robust for different finite element meshes and different Poissonnoise levels.

关键词： Fluorescence molecular tomography sparse regularization reconstruction algorithm least absolute shrinkage and selection operator.

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Comparative study of fully three-dimensional reconstruction algorithms for lens-free microscopy

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APPLIED OPTICS 2017年第13期56卷 3939-3951页

作者： Berdeu, Anthony Momey, Fabien Laperrousaz, Bastien Bordy, Thomas Gidrol, Xavier Dinten, Jean-Marc Picollet-D'hahan, Nathalie Allier, Cedric Univ Grenoble Alpes F-38000 Grenoble France Commissariat Energie Atom & Energies Alternat Lab Elect & Technol Informat F-38054 Grenoble France Univ Jean Monnet Lab Hubert Curien F-42100 St Etienne France Commissariat Energie Atom & Energies Alternat Inst Biosci & Biotechnol Grenoble F-38054 Grenoble France INSERM U1038 F-38054 Grenoble France

We propose a three-dimensional (3D) imaging platform based on lens-free microscopy to perform multiangle acquisitions on 3D cell cultures embedded in extracellular matrices. Lens-free microscopy acquisitions present some inherent issues such as the lack of phase information on the sensor plane and a limited angular coverage. We developed and compared three different algorithms based on the Fourier diffraction theorem to obtain fully 3D reconstructions. These algorithms present an increasing complexity associated with a better reconstruction quality. Two of them are based on a regularized inverse problem approach. To compare the reconstruction methods in terms of artefact reduction, signal-to-noise ratio, and computation time, we tested them on two experimental datasets: an endothelial cell culture and a prostate cell culture grown in a 3D extracellular matrix with large reconstructed volumes up to similar to 5 mm(3) with a resolution sufficient to resolve isolated single cells. The lens-free reconstructions compare well with standard microscopy. (C) 2017 Optical Society of America

关键词： Computerized tomography, 3 dimensional reconstruction computational time Inverse method Cell culture sensor aircraft reconstruction algorithm

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FBP-type CT reconstruction algorithms for triple-source circular trajectory with different scanning radii

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JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2019年第4期27卷 665-684页

作者： Chen, Ming Wang, Dan Cai, Ning Xia, Dimeng Zou, Jing Yu, Hengyong Shandong Univ Sci & Technol Coll Math & Syst Sci Qingdao 266590 Shandong Peoples R China Tianjin Univ State Key Lab Precis Measuring Technol & Instrume Tianjin Peoples R China Univ Massachusetts Lowell Dept Elect & Comp Engn Lowell MA 01854 USA

Multi-source computed tomography (CT) imaging has unique technical advantages not only for dynamic objects, but also for large-size objects by designing its imaging scan mode. Using the triple-source fan-beam imaging scan mode under three circular trajectories with two different radii, we in this study developed and analyzed theoretically several exact reconstruction algorithms in terms of full-scan and short-scan for three sets of truncated projection data. This triple-source scan configuration in different radii cases is easier to be simulated by a single-source scan configuration in an industrial CT system. The proposed algorithms are based on the idea of filtering-back-projection (FBP) algorithm, and can reconstruct the large-size objects under the same CT devices. The developed algorithms avoid data rebinning and can provide exact and fast image reconstruction. The results of the numerical simulation based data analysis verified that new algorithms were accurate and effective.

关键词： CT imaging scanning mode reconstruction algorithm FBP algorithm triple-source CT

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Quantitative analysis of emphysema in 3D using MDCT: Influence of different reconstruction algorithms

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EUROPEAN JOURNAL OF RADIOLOGY 2008年第2期65卷 228-234页

作者： Ley-Zaporozhan, Julia Ley, Sebastian Weinheirner, Oliver Iliyushenko, Svitlana Erdugan, Serap Eberhardt, Ralf Fuxa, Adelheid Mews, Juergen Kauczor, Hans-Ulrich Johannes Gutenberg Univ Hosp Dept Radiol D-55131 Mainz Germany German Canc Res Ctr Dept Radiol E 010 D-69120 Heidelberg Germany Univ Heidelberg Dept Pediat Radiol Heidelberg Germany Thoraxklin Dept Pulm Heidelberg Germany

Purpose: The aim of the study was to compare the influence of different reconstruction algorithms on quantitative emphysema analysis in patients with severe emphysema. Material and methods: Twenty-five patients suffering from severe emphysema were included in the study. All patients underwent inspiratory MDCT (Aquilion-16, slice thickness 1/0.8 mm). The raw data were reconstructed using six different algorithms: bone kernel with beam hardening correction (BHC), soft tissue kernel with BHC;standard soft tissue kernel, smooth soft tissue kernel (internal reference standard), standard lung kernel, and high-convolution kernel. The only difference between image data sets was the algorithm employed to reconstruct the raw data, no additional radiation was required. CT data were analysed using self-written emphysema detection and quantification software providing lung volume, emphysema volume (EV), emphysema index (EI) and mean lung density (MLD). Results: The use of kernels with BHC led to a significant decrease in MLD (5%) and EI (61-79%) in comparison with kernels without BHC. The absolute difference (from smooth soft tissue kernel) in MLD ranged from -0.6 to -6.1 HU and were significant different for all kernels. The EV showed absolute differences between -0.05 and -0.4 L and was significantly different for all kernels. The EI showed absolute differences between -0.8 and -5.1 and was significantly different for all kernels. Conclusion: The use of kernels with BHC led to a significant decrease in MLD and EI. The absolute differences between different kernels without BHC were small but they were larger than the known interscan variation in patients. Thus, for follow-up examinations the same reconstruction algorithm has to be used and use of BHC has to be avoided. (C) 2007 Elsevier Ireland Ltd. All rights reserved.

关键词： lung emphysema computed tomography emphysema detection software reconstruction algorithm pulmonary function tests

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PERFORMANCE ANALYSIS OF reconstruction algorithmS FOR PACKET VOICE COMMUNICATIONS

COMPUTER NETWORKS AND ISDN SYSTEMS

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COMPUTER NETWORKS AND ISDN SYSTEMS 1994年第11期26卷 1385-1408页

作者： CHO, YJ UN, CK GSIC NETWORK GRP C&C DEV LAB Kyonggi Do 430080 SOUTH KOREA KOREA ADV INST SCI & TECHNOL DEPT ELECT ENGN COMMUN RES LAB YUSONG GU TAEJON 30701 SOUTH KOREA

In this paper, we investigate two packet voice reconstruction algorithms in packet voice communications. The main difference between the two algorithms is that in algorithm I the play-out epoch of packets at the receiver is fixed, whereas algorithm Il it can be changed according to packet delays. We analyze these algorithms by obtaining the probability distributions of gap duration, silence reconstruction measure, resequencing buffer delay, and overall delay that are believed to represent effectively various aspects of the reconstruction behavior in a packetized voice transmission system. Then, we give numerical results and discuss several distinct aspects of the two algorithms.

关键词： PACKET VOICE COMMUNICATIONS reconstruction algorithm TALKSPURT SILENCE RESEQUENCING DELAY PACKET VOICE PROTOCOL

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A theoretical model for EM-ML reconstruction algorithms applied to rotating PET scanners

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PHYSICS IN MEDICINE AND BIOLOGY 2009年第7期54卷 1909-1934页

作者： Iriarte, A. Sorzano, C. O. S. Carazo, J. M. Rubio, J. L. Marabini, R. Univ Autonoma Madrid Escuela Politecn Super E-28049 Madrid Spain Univ Autonoma Madrid Ctr Nacl Biotecnol E-28049 Madrid Spain Univ San Pablo CEU Bioengn Lab Boadilla Del Monte Madri 28668 Spain Univ Politecn Madrid ETSI Telecomunicac Dpto Ingn Elect Biomed Image Technol Grp E-28040 Madrid Spain Networking Res Ctr Bioengn Biomat & Nanomed CIBER Madrid Spain

In this paper we show how to compute the normalizing and the system matrix terms of the EM-ML reconstruction algorithm for rotating planar detector PET scanners. The method introduced is valid for either pixelated or continuous scintillators. We base our computations in geometrical considerations, but other effects of the PET process can be easily included. In this regard, the intrinsic resolution of the detection system, the depth of interaction (DOI) of the incident gamma rays and the efficiency of the scintillators have been modeled in our development. The computation of the normalizing term and the system matrix is valid for any basis function used for the discrete approximation of the radionuclide concentration. We show that our computations are comparable to those of a Monte Carlo method at a small fraction of the computational cost.

关键词： electronic monitoring of offenders Positron emission tomography unit algorithms Valid Scintillators Monte Carlo technique discrete approximation radionuclide concentration reconstruction algorithm Theoretical Models algorithms Gamma Rays Detection systems Positron Emission Tomography Systems basis functions normalising

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Noise histogram regularization for iterative image reconstruction algorithms

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JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION 2007年第3期24卷 608-617页

作者： Thurman, Samuel T. Fienup, James R. Univ Rochester Inst Opt Rochester NY 14627 USA

We derive a regularization term for iterative image reconstruction algorithms based on the histogram of the residual difference between a forward-model image of a given object estimate and noisy image data. The term can be used to constrain this residual histogram to be statistically equivalent to the expected noise histogram, preventing overfitting of noise in a reconstruction. reconstruction results from simulated imagery are presented for the cases of Gaussian and quantization noise. (c) 2007 Optical Society of America.

关键词： histograms image data image reconstruction quantization noise Gauss Iterative reconstruction algorithm

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Experimental evaluation of reconstruction algorithms for scintillation crystal array based on charge projection readout

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NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 2019年第0期937卷 117-124页

作者： Shi, Rengang Chen, Ying Dang, Xiaojun Zhu, Balin Wang, Zhonghai Yang, Chaowen Wei, Mengfu China Acad Engn Phys Inst Mat Mianyang 621907 Sichuan Peoples R China Sichuan Univ Dept Nucl Engn & Technol Chengdu 610064 Sichuan Peoples R China

Although the technological advances in hardware of gamma camera lead to an obvious increase of detector performance, the final reconstructed image is still strongly restricted by reconstruction algorithms. In this work, an experiment evaluation of four popular algorithms, i.e., truncated Center-of-Gravity (TCOG), Raise-to-Power (RTP), Least Squares Estimator based on Particle Swarm Optimization (PSO-LSE) and Gaussian fitting (GF), for estimating the position of scintillation events detected by scintillation crystal array based on charge projection readout is performed. The detector of the gamma camera consists of a 22x22 array of CsI(Tl) scintillation crystals and an 8x8 matrix of SiPM pixels. The readout circuit, known as symmetric charge division (SCD) circuit, reduces an 8x8 array of signal channels into 8+8 signal channels coming from rows and columns projections. The imaging performances, in terms of flood image, average peak-to-valley ratio of line profile, useful field-of-view (UFOV) and position linearity response are measured. The result indicates that the four presented algorithms show good applicability for charge projection readout. RTP and PSO-LSE algorithms perform better in pixel identification of flood image and peak-to-valley of line profile, and PSO-LSE and GF methods are helpful to increase the UFOV. Among the four implemented reconstruction algorithms, PSO-LSE is a potential and promising algorithm that allows achieving excellent pixel identification of flood image, peak-to-valley ratio of line profile, spatial resolution, UFOV and position linearity response at the same time. The application of the PSO-LSE algorithm may offer the possibility to obtain high-quality reconstructed image in scintillation crystal array based on charge projection readout.

关键词： Gamma camera reconstruction algorithm Scintillator array Silicon photomultiplier Charge projection readout

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A DUAL MESH SCHEME FOR FINITE-ELEMENT BASED reconstruction algorithmS

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IEEE TRANSACTIONS ON MEDICAL IMAGING 1995年第3期14卷 504-514页

作者： PAULSEN, KD MEANEY, PM MOSKOWITZ, MJ SULLIVAN, JM NORRIS COTTON CANC CTR HANOVERNH 03755 WORCESTER POLYTECH INST WORCESTERMA 01609

The finite element (FE) method has found several applications in emerging imaging modalities, especially microwave imaging which has been shown to be potentially useful in a number of areas including thermal estimation. In monitoring temperature distributions, the biological phenomena of temperature variations of tissue dielectric properties is exploited, By imaging these properties and their changes during such therapies as hyperthermia, temperature distributions can be deduced using difference imaging techniques, This paper focuses on a microwave imaging problem where the hybrid element (HE) method is used in conjunction with a dual mesh scheme in an effort to image complex wavenumbers, k(2). The dual mesh scheme is introduced to improve the reconstructed images of tissue properties and is ideally suited for systems using FE methods as their computational base. Since the electric fields typically vary rapidly over a given body when irradiated by high-frequency electromagnetic sources, a dense mesh is needed for these fields to be accurately represented, Conversely, k(2) may be fairly constant over subregions of the body which would allow for a less dense sampling of this parameter in those regions, In the dual mesh system employed, the first mesh, which is uniformly dense, is used for calculating the electric fields over the body whereas the second mesh, which is nonuniform and less dense, is used for representing the k(2) distribution within the region of interest. This paper examines the 2-D TM polarization case for a pair of dielectric distributions on both a large and small problem to demonstrate the flexibility of the dual mesh method along with some of the difficulties associated with larger imaging problems, Results demonstrate the capabilities of the dual mesh concept in comparison to a single mesh approach for a variety of test cases, suggesting that the dual mesh method is critical for FE based image reconstruction where rapidly varying physical quantiti

关键词： reconstruction algorithm mesh method CASING INSPECTION Body GTF2E1 gene Microwave imaging Iron dual mesh FINITE ELEMENT Surgical Mesh

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Cone-beam and fan-beam image reconstruction algorithms based on spherical and circular harmonics

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PHYSICS IN MEDICINE AND BIOLOGY 2004年第11期49卷 2239-2256页

作者： Zeng, GSL Gullberg, GT Univ Utah Utah Ctr Adv Imaging Res Salt Lake City UT 84108 USA EO Lawrence Berkeley Natl Lab Berkeley CA 94720 USA

A cone-beam image reconstruction algorithm using spherical harmonic expansions is proposed. The reconstruction algorithm is in the form of a summation of inner products of two discrete arrays of spherical harmonic expansion coefficients at each cone-beam point of acquisition. This form is different from the common filtered backprojection algorithm and the direct Fourier reconstruction algorithm. There is no re-sampling of the data, and spherical harmonic expansions are used instead of Fourier expansions. As a special case, a new fan-beam image reconstruction algorithm is also derived in terms of a circular harmonic expansion. Computer simulation results for both cone-beam and fan-beam algorithms are presented for circular planar orbit acquisitions. The algorithms give accurate reconstructions;however, the implementation of the cone-beam reconstruction algorithm is computationally intensive. A relatively efficient algorithm is proposed for reconstructing the central slice of the image when a circular scanning orbit is used.

关键词： reconstruction algorithm Summation harmonic expansion Sphericity Resampling fan beam cone beam algorithms image reconstruction

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