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Whole-body PET parametric imaging employing direct 4D nested reconstruction and a generalized non-linear Patlak model

Nicolas A. Karakatsanis, Arman Rahmim, Bruce R. Whiting, Christoph Hoeschen
2014 Medical Imaging 2014: Physics of Medical Imaging  
Recently, we proposed a multi-bed dynamic acquisition framework enabling clinically feasible whole-body parametric PET imaging by employing post-reconstruction parameter estimation.  ...  We have developed a novel whole-body PET parametric reconstruction framework in the STIR platform, a widely employed open-source reconstruction toolkit, a) enabling accelerated convergence of direct 4D  ...  Charalampos Tsoumpas for the guidance they provided regarding the usage of the basic STIR package. This work was in part supported by the NIH grant 1S10RR023623.  ... 
doi:10.1117/12.2043918 fatcat:66kzytc6tfffzetylbawup7p6y

Validation of a Fast Block-Iterative Spatio-temporal Reconstruction Algorithm for Small Animal Dynamic PET Data

Tatsuya KON, Takashi OBI, Muneyuki SAKATA, Nagaaki OHYAMA, Yuichi KIMURA
2014 Advanced Biomedical Engineering  
Spatio-temporal reconstruction methods for positron emission tomography estimate the tissue timeactivity curves that are required for functional imaging.  ...  A parametric image of regional glucose metabolism reconstructed from the proposed method was almost identical to those obtained from conventional reconstruction algorithms.  ...  From the reconstructed tTACs, we produced parametric images by means of the Patlak graphic plot analysisz1|that generates parametric images of 18 F-FDGinflux values Ki.  ... 
doi:10.14326/abe.3.7 fatcat:bvkmfnyhwraj3h2kg4z4owucay

Whole-body direct 4D parametric PET imaging employing nested generalized Patlak expectation–maximization reconstruction

Nicolas A Karakatsanis, Michael E Casey, Martin A Lodge, Arman Rahmim, Habib Zaidi
2016 Physics in Medicine and Biology  
In the present study, we implemented, within the open-source software for tomographic image reconstruction platform, a clinically adoptable 4D WB reconstruction framework enabling efficient estimation  ...  Post-reconstruction standard Patlak (sPatlak) WB graphical analysis utilizes multi-bed multi-pass PET acquisition to produce quantitative WB images of the tracer influx rate K i as a complimentary metric  ...  Acknowledgments The authors would like to thank Drs Kris Thielemans and Charalampos Tsoumpas for their feedback regarding the software versioning and control procedures to facilitate integration of our  ... 
doi:10.1088/0031-9155/61/15/5456 pmid:27383991 pmcid:PMC5884686 fatcat:xd42t4yxbfdepcixkmjw4qd4fe

Quantitative PET image reconstruction employing nested expectation-maximization deconvolution for motion compensation

Nicolas A. Karakatsanis, Charalampos Tsoumpas, Habib Zaidi
2017 Computerized Medical Imaging and Graphics  
In addition, metabolic uptake rate K i parametric images were generated with the standard Patlak method.  ...  Subsequently, we replaced the integrated model component with a nested iterative Richardson-Lucy (RL) imagebased deconvolution method to accelerate the MLEM algorithm convergence rate (RL-3D-MCIR).  ...  The proof for those solutions has been previously discussed in MLEM applications of the optimization transfer theory and in analogous work for nested PSF-3D-MLEM algorithms [29] , [30] .  ... 
doi:10.1016/j.compmedimag.2016.11.006 pmid:27887989 fatcat:toa7hafrwnbsffx62yzhyp3fzu

Direct 4D parametric imaging for linearized models of reversibly binding PET tracers using generalized AB-EM reconstruction

Arman Rahmim, Yun Zhou, Jing Tang, Lijun Lu, Vesna Sossi, Dean F Wong
2012 Physics in Medicine and Biology  
As such, the focus of this work has been to develop a novel direct 4D parametric image reconstruction scheme for such tracers.  ...  As validation, the means of parameters estimated from 55 human 11 C-raclopride dynamic PET studies were 0031-9155/12/030733+23$33.00  ...  The authors also wish to thank Andrew Crabb for computational support, and Hiroto Kuwabara and Anil Kumar for help with delineation of ROIs in patient study.  ... 
doi:10.1088/0031-9155/57/3/733 pmid:22252120 pmcid:PMC3434225 fatcat:npyf4fqc5rcbji4ctb2vfvbshu

Evaluation of a direct 4D reconstruction method using generalised linear least squares for estimating nonlinear micro-parametric maps

Georgios I. Angelis, Julian C. Matthews, Fotis A. Kotasidis, Pawel J. Markiewicz, William R. Lionheart, Andrew J. Reader
2014 Annals of Nuclear Medicine  
Methods In this work we employed a recently proposed direct parametric image reconstruction algorithm to estimate the parametric maps of all micro-parameters of a two-tissue compartment model, used to  ...  Conclusions The proposed direct parametric reconstruction algorithm is a promising approach towards the estimation of all individual microparameters of any compartment model.  ...  The optimal number of internal iterations depends on two factors: (a) the initial estimate for the weights and (b) the level of noise in the TAC to be fitted.  ... 
doi:10.1007/s12149-014-0881-2 pmid:25073760 fatcat:nkz5m6ycqncqzjogsz3ok6rkdq

Generalized whole-body Patlak parametric imaging for enhanced quantification in clinical PET

Nicolas A Karakatsanis, Yun Zhou, Martin A Lodge, Michael E Casey, Richard L Wahl, Habib Zaidi, Arman Rahmim
2015 Physics in Medicine and Biology  
Validation on patient datasets demonstrated clinical feasibility for all Patlak methods, while TBR and CNR evaluations confirmed our simulation findings, and suggested presence of non-negligible k loss  ...  Institute of Physics and Engineering in Medicine for gPatlak. Bias of sPatlak was found to be 16-18% and 20-40% poorer than gPatlak for ROIs A and B, respectively.  ...  Acknowledgments The authors would like to thank Dr Abdel K Tahari and John Crandall for assistance in recruiting patients.  ... 
doi:10.1088/0031-9155/60/22/8643 pmid:26509251 pmcid:PMC4710061 fatcat:g2fv3nnekjfx7e3qxebm7jqbqa

STIR: Software for Tomographic Image Reconstruction Release 2

Kris Thielemans, Sanida Mustafovic, Charalampos Tsoumpas
2006 2006 IEEE Nuclear Science Symposium Conference Record  
We present a new version of STIR, an Open Source object-oriented library implemented in C++ for 3D PET reconstruction.  ...  This second release enhances its flexibility and modular design and includes additional features such as Compton scatter simulation, an additional iterative reconstruction algorithm and parametric image  ...  Dr Tsoumpas wishes to express his gratitude to Dr Loudos (Technological Educational Institute of Athens) for longstanding inspiring discussions.  ... 
doi:10.1109/nssmic.2006.354345 fatcat:j2euobthibdardbidrqbezu43e

Dynamic PET Image Reconstruction Incorporating Multiscale Superpixel Clusters

Shuangliang Cao, Yuru He, Hongyan Zhang, Wenbing Lv, Lijun Lu, Wufan Chen
2021 IEEE Access  
The curves were plotted by varying the iteration number from 20 to 100 for the MLEM algorithm and kernel method and varying the regularization parameter for the Bowsher method and proposed method.  ...  L   x x y x (3) However, the ML estimate can be very noisy at convergence.  ... 
doi:10.1109/access.2021.3058807 fatcat:y4l3owpq4fagpeezc23mjnrbqm

Towards enhanced PET quantification in clinical oncology

Habib Zaidi, Nicolas Karakatsanis
2018 British Journal of Radiology  
(4D) parametric imaging methods in clinical oncology.  ...  avenues for clinical diagnosis, assessment of response to treatment and therapy planning.  ...  iterative reconstruction routine within each iteration step of the frame-by-frame dynamic PET tomographic reconstruction method for accelerated convergence. 71, 98 Moreover, direct 4D parametric imaging  ... 
doi:10.1259/bjr.20170508 pmid:29164924 fatcat:7gtiavdgtzad3g6q7sos2orhx4

Direct parametric reconstruction in dynamic PET myocardial perfusion imaging:in vivostudies

Yoann Petibon, Yothin Rakvongthai, Georges El Fakhri, Jinsong Ouyang
2017 Physics in Medicine and Biology  
Direct 4D PET MLEM reconstruction of parametric images using the simplified reference tissue model with the basis function method for [11C]raclopride Paul Gravel and Andrew J Reader Abstract An overview  ...  By viewing 4D image reconstruction as a matter of either linear or non-linear parameter estimation for a set of spatiotemporal functions chosen to approximately represent the radiotracer distribution,  ...  Finally, the authors acknowledge Karl Herholz and Matthew Jones (University of Manchester, Wolfson Molecular Imaging Centre) for the raw PET list-mode data acquired with the HRRT used for figure 13.  ... 
doi:10.1088/1361-6560/aa6394 pmid:28379843 pmcid:PMC5739089 fatcat:gokrwq2x25hrthjjqdcbgaesnq

4D image reconstruction for emission tomography

Andrew J Reader, Jeroen Verhaeghe
2014 Physics in Medicine and Biology  
Finally, the authors acknowledge Karl Herholz and Matthew Jones (University of Manchester, Wolfson Molecular Imaging Centre) for the raw PET list-mode data acquired with the HRRT used for figure 13.  ...  The authors gratefully acknowledge the use of time activity curve data supplied by Paul Gravel for the simulation section, and previous informal discussions with Julian Matthews regarding the expectation  ...  Results of direct parametric reconstruction of the K i macro-parameter using the linear Patlak model and simulated brain data for [ 18 F]FDG can be found in Tsoumpas et al (2008b) (averaged reduction  ... 
doi:10.1088/0031-9155/59/22/r371 pmid:25361380 fatcat:dbhq74hapvbcfkkwjn2tkulumi

High Temporal-Resolution Dynamic PET Image Reconstruction Using A New Spatiotemporal Kernel Method [article]

Guobao Wang
2018 bioRxiv   pre-print
Current clinical dynamic PET has an effective temporal resolution of 5-10 seconds, which can be adequate for traditional compartmental modeling but is inadequate for exploiting the benefit of more advanced  ...  However, reconstruction of these short-time frames from tomographic data is extremely challenging as the count level of each frame is very low and high noise presents in both spatial and temporal domains  ...  (13) Note that the EM solution converges to the ML estimate when n is large, which however can result in noisy reconstruction.  ... 
doi:10.1101/323394 fatcat:lnud4th2yjds5ojmqb6dqg537y

Direct 4-D PET List Mode Parametric Reconstruction With a Novel EM Algorithm

Jianhua Yan, B. Planeta-Wilson, R. E. Carson
2012 IEEE Transactions on Medical Imaging  
This paper presents a direct 4-D method for producing 3-D images of kinetic parameters from list mode PET data.  ...  image reconstruction.  ...  [10] proposed direct parametric image reconstruction methods, whose compartment model is linear (Patlak plot), and is thus limited to irreversible tracers such as FDG. Furthermore, Rahmim et al.  ... 
doi:10.1109/tmi.2012.2212451 pmid:22929383 pmcid:PMC3660152 fatcat:npymfjhia5hszlwrredvtfup2e

4D-PET reconstruction using a spline-residue model with spatial and temporal roughness penalties

George P Ralli, Michael A Chappell, Daniel R McGowan, Ricky A Sharma, Geoff S Higgins, John D Fenwick
2018 Physics in Medicine and Biology  
Compared to conventional MAP reconstruction, spline-residue-based 4D reconstruction achieved >50% improvements for five of the eight combinations of the four kinetics parameters for which parametric maps  ...  (TACs) during the reconstruction, though the optimal choice of function remains an open question.  ...  The views expressed are those of the authors and not necessarily those of the NHS, the NIHR, HEE or the Department of Health.  ... 
doi:10.1088/1361-6560/aabb62 pmid:29616663 pmcid:PMC5983307 fatcat:4n4v4uxzyvho5acf2ouxrr35gi
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