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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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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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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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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 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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Advanced reconstruction algorithms for electron tomography: From comparison to combination

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ULTRAMICROSCOPY 2013年 127卷 40-47页

作者： Goris, B. Roelandts, T. Batenburg, K. J. Mezerji, H. Heidari Bals, S. Univ Antwerp EMAT B-2020 Antwerp Belgium Univ Antwerp Vis Lab B-2610 Antwerp Belgium Ctr Wiskunde & Informat NL-1098 XG Amsterdam Netherlands

In this work, the simultaneous iterative reconstruction technique (SIRT), the total variation minimization (TVM) reconstruction technique and the discrete algebraic reconstruction technique (DART) for electron tomography are compared and the advantages and disadvantages are discussed. Furthermore, we describe how the result of a three dimensional (3D) reconstruction based on TVM can provide objective information that is needed as the input for a DART reconstruction. This approach results in a tomographic reconstruction of which the segmentation is carried out in an objective manner. (c) 2012 Elsevier B.V. All rights reserved.

关键词： Electron tomography Total variation minimization Discrete algebraic reconstruction technique reconstruction algorithm

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Improvement of fluorescence-enhanced optical tomography with improved optical filtering and accurate model-based reconstruction algorithms

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JOURNAL OF BIOMEDICAL OPTICS 2011年第12期16卷 126002页

作者： Lu, Yujie Zhu, Banghe Darne, Chinmay Tan, I-Chih Rasmussen, John C. Sevick-Muraca, Eva M. Univ Texas Hlth Sci Ctr Houston Ctr Mol Imaging Inst Mol Med Houston TX 77030 USA

The goal of preclinical fluorescence-enhanced optical tomography (FEOT) is to provide three-dimensional fluorophore distribution for a myriad of drug and disease discovery studies in small animals. Effective measurements, as well as fast and robust image reconstruction, are necessary for extensive applications. Compared to bioluminescence tomography (BLT), FEOT may result in improved image quality through higher detected photon count rates. However, background signals that arise from excitation illumination affect the reconstruction quality, especially when tissue fluorophore concentration is low and/or fluorescent target is located deeply in tissues. We show that near-infrared fluorescence (NIRF) imaging with an optimized filter configuration significantly reduces the background noise. Model-based reconstruction with a high-order approximation to the radiative transfer equation further improves the reconstruction quality compared to the diffusion approximation. Improvements in FEOT are demonstrated experimentally using a mouse-shaped phantom with targets of pico- and subpico-mole NIR fluorescent dye. (C) 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3659291]

关键词： fluorescence-enhanced optical tomography excitation light rejection simplified spherical harmonics approximations finite element methods reconstruction algorithm parallel computation

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Quantitatively assessed CT imaging measures of pulmonary interstitial pneumonia: Effects of reconstruction algorithms on histogram parameters

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EUROPEAN JOURNAL OF RADIOLOGY 2010年第1期74卷 142-146页

作者： Koyama, Hisanobu Ohno, Yoshiharu Yamazaki, Youichi Nogami, Munenobu Kusaka, Akiko Murase, Kenya Sugimura, Kazuro Hyogo Kaibara Hosp Dept Radiol Kaibara Tanba 6693395 Japan Kobe Univ Dept Radiol Grad Sch Med Chuo Ku Kobe Hyogo 6500017 Japan Kobe Univ Hosp Div Radiol Chuo Ku Kobe Hyogo 6500017 Japan Osaka Univ Grad Sch Med Fac Hlth Sci Dept Med Phys & Engn Suita Osaka 5650871 Japan Inst Biomed Res & Innovat Div PET Chuo Ku Kobe Hyogo 6500047 Japan

This study aimed the influences of reconstruction algorithm for quantitative assessments in interstitial pneumonia patients. A total of 25 collagen vascular disease patients (nine male patients and 16 female patients;mean age, 57.2 years;age range 32-77 years) underwent thin-section MDCT examinations, and MDCT data were reconstructed with three kinds of reconstruction algorithm (two high-frequencies [A and B] and one standard [C]). In reconstruction algorithm B, the effect of low-and middle-frequency space was suppressed compared with reconstruction algorithm A. As quantitative CT parameters, kurtosis, skewness, and mean lung density (MLD) were acquired from a frequency histogram of the whole lung parenchyma in each reconstruction algorithm. To determine the difference of quantitative CT parameters affected by reconstruction algorithms, these parameters were compared statistically. To determine the relationships with the disease severity, these parameters were correlated with PFTs. In the results, all the histogram parameters values had significant differences each other (p < 0.0001) and those of reconstruction algorithm C were the highest. All MLDs had fair or moderate correlation with all parameters of PFT (-0.64 < r <-0.45, p < 0.05). Though kurtosis and skewness in high-frequency reconstruction algorithm A had significant correlations with all parameters of PFT (-0.61 < r <-0.45, p < 0.05), there were significant correlations only with diffusing capacity of carbon monoxide (DLco) and total lung capacity (TLC) in reconstruction algorithm C and with forced expiratory volume in 1 s (FEV1), DLco and TLC in reconstruction algorithm B. In conclusion, reconstruction algorithm has influence to quantitative assessments on chest thin-section MDCT examination in interstitial pneumonia patients. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

关键词： Lung CT reconstruction algorithm Interstitial pneumonia

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reconstruction of plant microstructure using distance weighted tessellation algorithm optimized by virtual segmentation

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JOURNAL OF STRUCTURAL BIOLOGY 2019年第2期208卷 115-126页

作者： Liu, Wangyu Zhang, Ling Huang, Jiale Xie, Weigui South China Univ Technol Sch Mech & Automot Engn Wushan Rd Guangzhou 510641 Guangdong Peoples R China Xiamen Univ Dept Mech & Elect Engn Xiamen 361005 Fujian Peoples R China

The accurate reconstruction model of plant microstructure is important for obtaining the mechanical properties of plant tissues. In this paper, a virtual segmentation technique is proposed to optimize Delaunay triangulation. Based on the optimized Delaunay triangulation, an Optimized Distance Weighted Tessellation (ODWT) algorithm is developed. Two different structures, namely carrot and retting maize vascular bundles, were reconstructed via the ODWT algorithm. The accuracy of ODWT is evaluated statistically by comparing with Centroid-based Voronoi Tessellation (CVT) and Area Weighted Tessellation (AWT). The results show that ODWT has distinct advantages over CVT and AWT. It is worth mentioning that ODWT has better performance than CVT when there exists large diversity in adjacent cell area. It is found that CVT and AWT fail to reconstruct cells with elongated and concave shapes, while ODWT shows excellent feasibility and reliability. Furthermore, ODWT is capable of establishing finite tissue boundary, which CVT and AWT have failed to realize. The purpose of this work is to develop an algorithm with higher accuracy to implement the preprocessing for further numerical study of plants properties. The comparison results of the simulated values of the longitudinal tensile modulus with the experimental value show that ODWT algorithm can improve the prediction accuracy of multi-scale models on mechanical properties.

关键词： Tessellation Geometry modelling Plant microstructure reconstruction algorithm

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Ray-tracing-based reconstruction algorithms for digital breast tomosynthesis

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JOURNAL OF ELECTRONIC IMAGING 2015年第2期24卷

作者： Zhou, Weihua Lu, Jianping Zhou, Otto Chen, Ying So Illinois Univ Dept Elect & Comp Engn Carbondale IL 62901 USA Univ N Carolina Dept Phys & Astron Chapel Hill NC 27599 USA Curriculum Appl Sci & Engn Chapel Hill NC 27599 USA Univ N Carolina Sch Med Lineberger Comprehens Canc Ctr Chapel Hill NC 27599 USA

As a breast-imaging technique, digital breast tomosynthesis has great potential to improve the diagnosis of early breast cancer over mammography. Ray-tracing-based reconstruction algorithms, such as ray-tracing back projection, maximum-likelihood expectation maximization (MLEM), ordered-subset MLEM (OS-MLEM), and simultaneous algebraic reconstruction technique (SART), have been developed as reconstruction methods for different breast tomosynthesis systems. This paper provides a comparative study to investigate these algorithms by computer simulation and phantom study. Experimental results suggested that, among the four investigated reconstruction algorithms, OS-MLEM and SART performed better in interplane artifact removal with a fast speed convergence. (C) 2015 SPIE and IS&T

关键词： digital breast tomosynthesis reconstruction algorithm ray-tracing

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Influence of different time framings, reconstruction algorithms and post-processing methods on the quantification of myocardial blood flow from ¹³N-NH3 PET images

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CLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING 2024年第2期44卷 154-163页

作者： Akil, Shahnaz Szekely, Anna E. Hedeer, Fredrik Olsson, Berit Engblom, Henrik Hindorf, Cecilia Lund Univ Skane Univ Hosp Dept Clin Sci Lund Clin Physiol Lund Sweden Lund Univ Dept Med Radiat Phys Lund Sweden Skane Univ Hosp Dept Clin Physiol S-22185 Lund Sweden

Background: The aim was to investigate to what extent the quantification of myocardial blood flow (MBF) from dynamic N-13-NH3 positron emission tomography (PET) images is affected by time frame schemes, time-of-flight (ToF), reconstruction algorithms, blood pool volume of interest (VOI) locations and compartment models in patients with suspected chronic coronary ***: A standard MBF value was determined from 25 patients' rest/stress N-13-NH3 PET/CT images reconstructed with ordered subset expectation maximization (OSEM), 5 s time frame for the first frames without ToF, subsequently analyzed using a basal VOI and the deGrado compartment model. MBFs calculated using 2 or 10 s for the first frames, ToF, block-sequential regularized expectation maximization (BSREM), apical or large VOI, Hutchins or Krivokapich compartment models were compared to MBFstandard in Bland-Altman plots (bias +/- SD).Results: Good agreement in global rest/stress MBF (mL/min/g) was found when changing the time frame scheme or reconstruction algorithm (MBFstandard vs. MBF2s: -0.02 +/- 0.06;MBF10s: 0.01 +/- 0.07;MBFBSREM: 0.01 +/- 0.07), while a lower level of agreement was found when altering the other factors (MBFstandard vs. MBFToF: -0.07 +/- 0.10;MBFapical VOI: -0.27 +/- 0.25;MBFlarge VOI: -0.11 +/- 0.10;MBFHutchins: -0.08 +/- 0.10;MBFKrivokapich: -0.47 +/- 0.50).Conclusions: Quantification of MBF from N-13-NH3 PET images is more affected by choice of compartment models, ToF and blood pool VOIs than by different time frame schemes and reconstruction algorithms.

关键词： chronic coronary syndrome compartment model myocardial blood flow positron emission tomography reconstruction algorithm time frame scheme time-of-flight

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