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Effects of acquisition method and reconstruction algorithm for CT number measurement on standard-dose CT and reduced-dose CT: a QIBA phantom study

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JAPANESE JOURNAL OF RADIOLOGY 2019年第5期37卷 399-411页

作者： Ohno, Yoshiharu Fujisawa, Yasuko Fujii, Kenji Sugihara, Naoki Kishida, Yuji Seki, Shinichiro Yoshikawa, Takeshi Kobe Univ Grad Sch Med Dept Radiol Div Funct & Diagnost Imaging ResChuo Ku 7-5-2 Kusunoki Cho Kobe Hyogo 6500017 Japan Kobe Univ Grad Sch Med Adv Biomed Imaging Res Ctr Kobe Hyogo Japan Canon Med Syst Corp Otawara Tochigi Japan Kobe Univ Grad Sch Med Dept Radiol Div Radiol Kobe Hyogo Japan

PurposeTo compare the effect of different acquisition and reconstruction methods on the radiation dose and accuracy of CT number measurements, using a 320-detector row CT and a Quantitative Imaging Biomarker Alliance (QIBA) recommended *** and methodsAcquisitions were performed on a 320-detector row CT, as 64- and 80-detector row helical and wide detector step-and-shoot (i.e., wide volume) acquisitions with tube currents of 400mA, 100mA, 50mA, 20mA, and 10mA. Image was reconstructed with the filtered back projection (FBP), adaptive iterative dose reduction using 3D processing (AIDR 3D), and forward projected model-based iterative reconstruction (FIRST) methods. The difference between measured CT numbers and the actual -856HU value of the phantom insert was determined by each CT acquisition protocol. Differences in actual and measured CT numbers were compared among acquisitions and among reconstruction methods by means of Tukey's HSD *** CT number obtained with 64-detector row helical acquisition was significantly larger than that obtained with others (p<0.0001). At each tube current, the CT number reconstructed with FIRST was significantly smaller than that with others (p<0.0001).ConclusionAcquisition and reconstruction methods are significantly affecting radiation dose reduction and accuracy of CT number measurements on a phantom study.

关键词： Lung CT Radiation dose reconstruction algorithm Scanning method

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A novel reconstruction algorithm based on density clustering for cosmic-ray muon scattering inspection

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NUCLEAR ENGINEERING AND TECHNOLOGY 2021年第7期53卷 2348-2356页

作者： Hou, Linjun Zhang, Quanhu Yang, Jianqing Cai, Xingfu Yao, Qingxu Huo, Yonggang Chen, Qifan Xian Res Inst Hitech Xian 710025 Peoples R China Spallat Neutron Source Sci Ctr Dongguan 523803 Guangdong Peoples R China

As a relatively new radiation imaging method, the cosmic-ray muon scattering imaging technology can be used to prevent nuclear smuggling and is of considerable significance to nuclear safety. Proposed in this paper is a new reconstruction algorithm based on density clustering, aiming to improve inspection quality with better performance. Firstly, this new algorithm is introduced in detail. Then in order to eliminate the inequity of the density threshold caused by the heterogeneity of the muon flux in different positions, a new flux correction method is proposed. Finally, three groups of simulation experiments are carried out with the help of Geant4 toolkit to optimize the algorithm parameters, verify the correction method and test the inspection quality under shielded condition, and compare this algorithm with another common inspection algorithm under different conditions. The results show that this algorithm can effectively identify and locate nuclear material with low misjudging and missing rates even when there is shielding and momentum precision is low, and the threshold correcting method is universally effective for density clustering algorithms. (c) 2021 Korean Nuclear Society, Published by Elsevier Korea LLC. This is an open access article under the CC BY-NC-ND license (http://***/licenses/by-nc-nd/4.0/).

关键词： Radiation imaging reconstruction algorithm Cosmic-ray muon Nuclear safety

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Ordered subset expectation maximisation vs Bayesian penalised likelihood reconstruction algorithm in 18F-PSMA-1007 PET/CT

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ANNALS OF NUCLEAR MEDICINE 2020年第3期34卷 192-199页

作者： Witkowska-Patena, Ewa Budzynska, Anna Gizewska, Agnieszka Dziuk, Miroslaw Walecka-Mazur, Agata Mil Inst Med Dept Nucl Med 128 Szaserow St PL-04141 Warsaw Poland Affidea Mazovian PET CT Med Ctr 128 Szaserow St PL-04349 Warsaw Poland Synektik Pharma Kielce Poland

Background The aim of the study was to compare widely used ordered subset expectation maximisation (OSEM) algorithm with a new Bayesian penalised likelihood (BPL) *** algorithm in 18F-PSMA-1007 PET/CT. Methods We retrospectively assessed 25 18F-PSMA-1007 PET/CT scans with both OSEM and *** reconstructions available. Each scan was independently reported by two physicians both in OSEM and ***. SUVmax, SUVmean and tumour-to-background ratio (TBR) of each lesion were measured. Reports were also compared for their final conclusions and the number and localisation of lesions. Results In both reconstructions the same 87 lesions were reported. Mean SUVmax, SUVmean and TBR were higher for *** than OSEM (7.01 vs 6.53 [p = 0.052], 4.16 vs 3.84 [p = 0.036] and 20.2 vs 16.8 [p < 0.00001], respectively). Small lesions (< 10 mm) had statistically significant higher SUVmax, SUVmean and TBR in *** than OSEM (5.37 vs 4.79 [p = 0.032], 3.08 vs 2.70 [p = 0.04] and 15.5 vs 12.5 [p = 0.00214], respectively). For lesions >= 10 mm, no significant differences were observed. Findings with higher tracer avidity (SUVmax >= 5) tended to have higher SUVmax, SUVmean and TBR values in *** (11.6 vs 10.3 [p = 0.00278], 7.0 vs 6.7 [p = 0.077] and 33.9 vs 26.7 [p < 0.00001, respectively). Mean background uptake did not differ significantly between *** and OSEM (0.42 vs 0.39, p = 0.07). Conclusions In 18F-PSMA-1007 PET/CT, *** SUVs and TBR tend to be higher (regardless of lesion localisation), especially for small and highly avid lesions. Increase in SUVs is also higher for lesions with high tracer uptake. Still, *** does not affect 18F-PSMA-1007 PET/CT specificity and sensitivity.

关键词： 18F-PSMA-1007 PET CT Prostate cancer Q Clear OSEM reconstruction algorithm

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reconstruction algorithm of super-resolution infrared image based on human vision processing mechanism

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Frontiers of Optoelectronics 2015年第2期8卷 195-202页

作者： Shaosheng DAI Zhihui DU Haiyan XIANG Jinsong LIU Chongqing Key Laboratory of Signal and Information Processing Chongqing University of Posts and Telecommunications Chongqing 400065 China

Aiming at solving the problem of low resolu- tion and visual blur in infrared imaging, a super-resolution infrared image reconstruction method using human vision processing mechanism （HVPM） was proposed. This method combined a mechanism of vision lateral inhibition with an algorithm projection onto convex sets （POCS） reconstruction, the improved vision lateral inhibition network was utilized to enhance the contrast between object and background of low-resolution image sequences, then POCS algorithm was adopted to reconstruct super- resolution image. Experimental results showed that the proposed method can significantly improve the visual effect of image, whose contrast and information entropy of reconstructed infrared images were improved by approxi- mately 5 times and 1.6 times compared with traditional POCS reconstruction algorithm, respectively.

关键词： human vision processing mechanism(HVPM) projection onto convex sets (POCS) super-resolution infrared image reconstruction algorithm

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A UWB-2PPM reconstruction algorithm Without A Priori Knowledge Of Pilot

A UWB-2PPM Reconstruction Algorithm Without A Priori Knowled...

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International Conference on Mechatronics Engineering and Computing Technology (ICMECT)

作者： Yin, Haibo Yang, Jun'an Gong, Jie Wang, Weidong Inst Elect Engn Hefei 230037 Anhui Peoples R China

ISBN: (纸本)9783038351153

Compressed Sensing is very efficient in reducing the relatively high sampling rate. But when it comes to the channel estimation of uncooperative communication, the common CS reconstruction algorithms seem impractical to implement since a pilot is required, which is difficult for uncooperative communication. In this paper, we combine the sparsity transform dictionary, which is formed by a sequence of delays of the template signal, together with the idea of alternative minimization to improve the traditional CoSaMP algorithm to reconstruct under-sampled UWB-2PPM signal transmitted by unkown complex channel without a knowledge of pilot. The theoretical analysis and simulations show that the proposed algorithm is capable of reconstructing the original transmitted signal without a pilot.

关键词： UWB non-cooperation compressed sensing reconstruction algorithm

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Improvement based on FDK reconstruction algorithm of conebeam CT

Improvement based on FDK reconstruction algorithm of conebea...

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Conference on Three-Dimensional and Multidimensional Microscopy - Image Acquisition and Processing XVII

作者： Miao, Hui Wang, Tingting Zhao, Huijuan Gao, Feng Tianjin Univ Coll Precis Instruments & Optoelect Engn Tianjin 300072 Peoples R China

ISBN: (纸本)9780819479662

As a typical 3D image algorithm, Feldkamp-David-Kress reconstruction algorithm is a filtered backprojection very similar to the 2D algorithm. Recent years, it has been widely used for its easy implementation and acceptable reconstruction precision for small cone-beam angle. For big cone-beam angles, however, the reconstruction exactness of horizontal planes will dramatically decrease with the distance from the central plane increases. Therefore, for improving the reconstruction precision in vertical direction, a similar reciprocal Gaussian function as the weighted factor was introduced into FDK algorithm in the article. The validity of the improved FDK algorithm was verified and evaluated through both the computer numerical simulation and the phantom model experiment. The quantitative analysis for the reconstruction results demonstrated that the reconstruction image using the improved FDK algorithm could primely revise the original reconstruction images and restore well closely to the tomography image of the prototype object.

关键词： FDK reconstruction cone-beam CT image reconstruction reconstruction algorithm

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A Novel reconstruction algorithm for Bioluminescent Tomography Based on Bayesian Compressive Sensing

A Novel Reconstruction Algorithm for Bioluminescent Tomograp...

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SPIE Biomedical Applications in Molecular, Structural and Functional Imaging Conference

作者： Wang, Yaqi Feng, Jinchao Jia, Kebin Sun, Zhonghua Wei, Huijun Beijing Univ Technol Coll Elect Informat & Control Engn Beijing 100022 Peoples R China

ISBN: (纸本)9781510600232

Bioluminescence tomography (BLT) is becoming a promising tool because it can resolve the biodistibution of bioluminescent reporters associated with cellular and subcellular function through several millimeters with to centimeters of tissues in vivo. However, BLT reconstruction is an ill-posed problem. By incorporating sparse a priori information about bioluminescent source, enhanced image quality is obtained for sparsity based reconstruction algorithm. Therefore, sparsity based BLT reconstruction algorithm has a great potential. Here, we proposed a novel reconstruction method based on Bayesian compressive sensing and investigated its feasibility and effectiveness with a heterogeneous phantom. The results demonstrate the potential and merits of the proposed algorithm.

关键词： Optical tomography Bioluminescence tomography (BLT) reconstruction algorithm Inverse Problem Sparsity Bayesian Compressive Sensing Diffusion approximation

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A Compressive Sensing reconstruction algorithm for Trinary and Binary Sparse Signals Using Pre-mappin

A Compressive Sensing Reconstruction Algorithm for Trinary a...

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Data Compression Conference (DCC)

作者： Zhang, Xinyu Chen, Zhuoyuan Wen, Jiangtao Ma, Jianwei Han, Yuxing Villasenor, John Tsinghua Univ Beijing Peoples R China Florida State Univ Tallahassee FL 32306 USA Univ Calif Los Angeles Los Angeles CA 90095 USA

ISBN: (纸本)9780769543529

In this paper, we first analyze impact of the distribution of sparse signals on reconstruction quality in compressive sensing through experimental results and heuristic analysis. We suggest that trinary/binary sparse signals are one of the most difficult signals to reconstruct in terms of error bounds. We then show that by incorporating linear or non-linear mapping prior to sensing, significant improvement in the recovery performance can be achieved.

关键词： reconstruction algorithm Compressed sensing heuristic analysis signals Binary

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Channel Estimation Based on Dual-path reconstruction algorithm 2021

Channel Estimation Based on Dual-path Reconstruction Algorit...

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2nd International Conference on Artificial Intelligence and Information Systems (ICAIIS )

作者： Han, Mingzhi An, Chengquan Gao, Bo Harbin Engn Univ Coll Informat & Commun Engn Harbin Peoples R China

ISBN: (纸本)9781450390200

In the sparse channel estimation of Orthogonal Frequency Division Multiplexing (OFDM) systems, for any delay of the multipath channels, most of the channel estimation algorithms based on Compressed Sensing (CS) have only one estimate. In view of this situation, a Dual-path reconstruction (DR) algorithm is proposed based on the Orthogonal Matching Pursuit with Binary-search Refinement (OMPBR) algorithm. When locating a time delay in the actual channel, the algorithm provides two estimators to estimate the time delay. Ideally, the actual time delay is in the middle of the two estimators, and the errors of the two estimators cancel each other out. Through theoretical analysis and simulation results, it is confirmed that the accuracy of channel estimation achieved by the DR algorithm is higher than that achieved by the OMPBR algorithm.

关键词： OFDM channel estimation compressed sensing reconstruction algorithm

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3-Dimensional stereo implementation of photoacoustic imaging based on a new image reconstruction algorithm without using discrete Fourier transform

3-Dimensional stereo implementation of photoacoustic imaging...

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Conference on Three-Dimensional Imaging, Visualization, and Display

作者： Ham, Woonchul Song, Chulgyu Chonbuk Natl Univ Fac Div Elect & Informat Jeonju South Korea

ISBN: (纸本)9781510609396;9781510609402

In this paper, we propose a new three-dimensional stereo image reconstruction algorithm for a photoacoustic medical imaging, system. We also introduce and discuss a new theoretical algorithm by using the physical concept of Radon transform. The main key concept of proposed theoretical algorithm is to evaluate the existence possibility of the acoustic source within a searching region by using the geometric distance between each sensor element of acoustic detector and the corresponding searching region denoted by grid. We derive the mathematical equation for the magnitude of the existence possibility which can be used for implementing a new proposed algorithm. We handle and derive mathematical equations of proposed algorithm for the one dimensional sensing array case as well as two dimensional sensing array case too. A mathematical k-wave simulation data are used for comparing the image quality of the proposed algorithm with that of general conventional algorithm in which the FFT should be necessarily used. From the k-wave Matlab simulation results, we can prove the effectiveness of the proposed reconstruction algorithm..

关键词： photoacoustic reconstruction algorithm k-wave medical imaging GPU NOS FFT

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