2023
Super-resolution in brain positron emission tomography using a real-time motion capture system
Chemli Y, Tétrault M, Marin T, Normandin M, Bloch I, El Fakhri G, Ouyang J, Petibon Y. Super-resolution in brain positron emission tomography using a real-time motion capture system. NeuroImage 2023, 272: 120056. PMID: 36977452, PMCID: PMC10122782, DOI: 10.1016/j.neuroimage.2023.120056.Peer-Reviewed Original ResearchConceptsBrain positron emission tomographySuper-resolutionEvent-by-event basisReal-time motion capture systemSR reconstruction methodTracking cameraVisualization of small structuresPET reconstruction algorithmMoving phantomMeasure target motionLine profilesPET/CT scannerMeasured shiftsImprove image resolutionMotion capture systemMotion tracking devicePositron emission tomographyReconstruction algorithmSpatial resolutionMeasured linesPhantomReal-timeEstimation frameworkIncreased spatial resolutionReconstruction method
2019
MR-based cardiac and respiratory motion correction of PET: application to static and dynamic cardiac 18F-FDG imaging
Petibon Y, Sun T, Han P, Ma C, Fakhri G, Ouyang J. MR-based cardiac and respiratory motion correction of PET: application to static and dynamic cardiac 18F-FDG imaging. Physics In Medicine And Biology 2019, 64: 195009. PMID: 31394518, PMCID: PMC7007962, DOI: 10.1088/1361-6560/ab39c2.Peer-Reviewed Original ResearchConceptsMR-based motion correctionRespiratory motion correctionMotion correctionImproved spatial resolutionReconstructed activity concentrationCardiac PET dataSpatial resolutionCoincidence eventsMR-basedPET imagingContrast-to-noise ratioCardiac PET imagingRespiratory phasesMC dataImprove image qualityMR acquisitionQuantitative accuracyCardiac PETPET dataActivity concentrationsMyocardium wallF-FDG PETDynamics studiesImage qualityMotion artifactsFree-Breathing Three-Dimensional T1 Mapping of the Heart Using Subspace-Based Data Acquisition and Image Reconstruction
Han P, Horng D, Marin T, Petibon Y, Ouyang J, Fakhri G, Ma C. Free-Breathing Three-Dimensional T1 Mapping of the Heart Using Subspace-Based Data Acquisition and Image Reconstruction. Annual International Conference Of The IEEE Engineering In Medicine And Biology Society (EMBC) 2019, 00: 4008-4011. PMID: 31946750, DOI: 10.1109/embc.2019.8856511.Peer-Reviewed Original ResearchConceptsRespiratory motionRespiratory gatingLongitudinal relaxation timeSubspace-based methodsLow-rank tensorMagnetic resonance imagingRelaxation timeT1 mappingT)-spaceSubspace-basedSparsity constraintDynamic MR imagingReconstructed mapsSpatiotemporal correlationThree-dimensionalCardiac MRHealthy subjectsIn vivo dataMagnetizationResonance imagingImage functionMR imagingData acquisitionClinical applicationTensor
2017
Direct parametric reconstruction in dynamic PET myocardial perfusion imaging: in vivo studies
Petibon Y, Rakvongthai Y, Fakhri G, Ouyang J. Direct parametric reconstruction in dynamic PET myocardial perfusion imaging: in vivo studies. Physics In Medicine And Biology 2017, 62: 3539-3565. PMID: 28379843, PMCID: PMC5739089, DOI: 10.1088/1361-6560/aa6394.Peer-Reviewed Original ResearchConceptsPET sinogramsSignal-to-noise ratioList-mode PET dataSiemens Biograph mMR scannerList-mode dataMyocardial perfusion imagingNoise realizationsPET myocardial perfusion imagingLow count levelsLeast-squares fitBiograph mMR scannerPET projection dataOriginal list-mode dataMyocardial blood flowCount levelsParametric reconstructionOSEMReconstruction methodIndependent noise realizationsNormal count levelsSinogramDirect reconstructionDynamic sinogramsKinetic modelPoor signal-to-noise ratio
2016
Investigation of cone-beam CT image quality trade-off for image-guided radiation therapy
Bian J, Sharp G, Park Y, Ouyang J, Bortfeld T, Fakhri G. Investigation of cone-beam CT image quality trade-off for image-guided radiation therapy. Physics In Medicine And Biology 2016, 61: 3317-3346. PMID: 27032676, DOI: 10.1088/0031-9155/61/9/3317.Peer-Reviewed Original ResearchConceptsImage-guided radiation therapyCone-beam CTFiltered-backprojectionImage quality trade-offConventional filtered-backprojectionShort-scan reconstructionsFiltered-backprojection algorithmFan-beam reconstructionTV-based algorithmIterative reconstruction algorithmCatphan phantomRadiation therapyAngular rangeTotal-variationOptimal exposure levelClinical scannerScanning configurationReconstruction algorithmImaging conditionsCatphanPhantomExposure levelsTherapyConfigurationRange
2014
Sparse-View Spectral CT Reconstruction Using Spectral Patch-Based Low-Rank Penalty
Kim K, Ye J, Worstell W, Ouyang J, Rakvongthai Y, Fakhri G, Li Q. Sparse-View Spectral CT Reconstruction Using Spectral Patch-Based Low-Rank Penalty. IEEE Transactions On Medical Imaging 2014, 34: 748-760. PMID: 25532170, DOI: 10.1109/tmi.2014.2380993.Peer-Reviewed Original ResearchConceptsLow-rank penaltySelf-similarity of patchesLog-likelihoodPoisson log-likelihoodCost functionSpectral CT reconstructionOriginal cost functionGPU implementationAlternating minimizationSensitive to intensity changesConventional algorithmsSpectral imagingEdge directionComputational costProcedure algorithmComputational advantagesAlgorithmX-ray transmissionComputer simulationsOptimization methodSpectral computed tomographySelf-similarityCT reconstructionX-rayGPU4D numerical observer for lesion detection in respiratory‐gated PET
Lorsakul A, Li Q, Trott C, Hoog C, Petibon Y, Ouyang J, Laine A, Fakhri G. 4D numerical observer for lesion detection in respiratory‐gated PET. Medical Physics 2014, 41: 102504. PMID: 25281979, PMCID: PMC4281099, DOI: 10.1118/1.4895975.Peer-Reviewed Original ResearchMeSH KeywordsAlgorithmsComputer SimulationFluorodeoxyglucose F18HumansImage Interpretation, Computer-AssistedLung DiseasesModels, BiologicalMonte Carlo MethodMotionPhantoms, ImagingPositron-Emission TomographyRadiopharmaceuticalsRegression AnalysisRespiratory-Gated Imaging TechniquesSignal-To-Noise RatioConceptsRespiratory-gated positron emission tomographyMotion-corrected imagesDetection signal-to-noise ratioLesion detection taskNumerical observationsLesion detection performanceSignal-to-noise ratioPositron emission tomography sinogramsSpherical lesionsHotelling observerMotion correction methodPositron emission tomographyGeant4 ApplicationTomographic EmissionChannelized Hotelling observerAnthropomorphic phantomScanner geometryOSEM algorithmMonte Carlo simulationsPET framesImprove lesion detectionLesion detectionSignal-to-noise ratio measurementsActivity distributionConventional 3D approachRelative role of motion and PSF compensation in whole‐body oncologic PET‐MR imaging
Petibon Y, Huang C, Ouyang J, Reese T, Li Q, Syrkina A, Chen Y, Fakhri G. Relative role of motion and PSF compensation in whole‐body oncologic PET‐MR imaging. Medical Physics 2014, 41: 042503. PMID: 24694156, PMCID: PMC3971824, DOI: 10.1118/1.4868458.Peer-Reviewed Original ResearchConceptsPoint spread function modelRespiratory motionPoint spread functionPET-MR scannersPencil-beam navigator echoesPET-MRMeasurement of respiratory motionPSF modelRespiratory motion correctionDetector blur effectsModel respiratory motionLung-liver interfacePatient studiesLesion contrastSimultaneous PET-MRSource of image degradationWhole-body PET imagingPET reconstruction algorithmMoving lesionsPhantom experiment resultsPET eventsContrast recoveryNavigator echoesIterative reconstruction processMotion correctionMyocardial Defect Detection Using PET-CT: Phantom Studies
Mananga E, Fakhri G, Schaefferkoetter J, Bonab A, Ouyang J. Myocardial Defect Detection Using PET-CT: Phantom Studies. PLOS ONE 2014, 9: e88200. PMID: 24505429, PMCID: PMC3914931, DOI: 10.1371/journal.pone.0088200.Peer-Reviewed Original ResearchMeSH KeywordsAlgorithmsEquipment DesignFemaleHumansMaleMyocardiumPhantoms, ImagingPositron-Emission TomographyConceptsMyocardial defect detectionFiltered back projectionChannelized Hotelling observerPhantom studyActivity distributionSubset expectation maximizationDefect detectionCardiac PET studiesMyocardial defectsHotelling observerNoise levelBack-projectionPET-CTPhantomExpectation maximizationOP-OSEMReconstruction schemePET studiesOSEMDefectsNoiseMotion compensation for brain PET imaging using wireless MR active markers in simultaneous PET–MR: Phantom and non-human primate studies
Huang C, Ackerman J, Petibon Y, Normandin M, Brady T, Fakhri G, Ouyang J. Motion compensation for brain PET imaging using wireless MR active markers in simultaneous PET–MR: Phantom and non-human primate studies. NeuroImage 2014, 91: 129-137. PMID: 24418501, PMCID: PMC3965607, DOI: 10.1016/j.neuroimage.2013.12.061.Peer-Reviewed Original ResearchConceptsMotion correctionWireless markersList-mode reconstructionReconstructed PET imagesMotion correction techniqueObserver signal-to-noise ratioSimultaneous PET-MRMotion artifactsPET phantomPET contrastPET reconstructionBrain PET imagingPET imagingPhantomBrain PETPET-MRIndependent noise realizationsAccurate quantitative valuesHead motionNoise realizationsPET dataSignal-to-noise ratioStatic referenceBrain PET scansActivation markers
2013
Simultaneous 99mTc‐MDP/123I‐MIBG tumor imaging using SPECT‐CT: Phantom and constructed patient studies
Rakvongthai Y, Fakhri G, Lim R, Bonab A, Ouyang J. Simultaneous 99mTc‐MDP/123I‐MIBG tumor imaging using SPECT‐CT: Phantom and constructed patient studies. Medical Physics 2013, 40: 102506. PMID: 24089927, PMCID: PMC3785531, DOI: 10.1118/1.4820977.Peer-Reviewed Original ResearchConceptsScatter correctionDual-radionuclideContrast recoveryPhantom studyAnthropomorphic torso phantomPatient studiesTumor uptakeTumor imagingSPECT projectionsTorso phantomMonte-CarloPhantom dataPhantomIterative reconstructionOSEMProjection dataDR dataIncrease patient throughputNoise realizationsSPECT-CTImage reconstructionClinical studiesTumorTumor projectionPoisson noiseDirect reconstruction of cardiac PET kinetic parametric images using a preconditioned conjugate gradient approach
Rakvongthai Y, Ouyang J, Guerin B, Li Q, Alpert N, Fakhri G. Direct reconstruction of cardiac PET kinetic parametric images using a preconditioned conjugate gradient approach. Medical Physics 2013, 40: 102501. PMID: 24089922, PMCID: PMC3779266, DOI: 10.1118/1.4819821.Peer-Reviewed Original Research
2010
Dual-Radionuclide Brain SPECT for the Differential Diagnosis of Parkinsonism
El Fakhri G, Ouyang J. Dual-Radionuclide Brain SPECT for the Differential Diagnosis of Parkinsonism. Methods In Molecular Biology 2010, 680: 237-246. PMID: 21153385, DOI: 10.1007/978-1-60761-901-7_16.Peer-Reviewed Original ResearchConceptsDopamine transporter functionBrain SPECTDifferential diagnosis of parkinsonismDifferential diagnosisDiagnosis of parkinsonismIdiopathic Parkinson's diseaseDifferential diagnosis of idiopathic Parkinson’s diseaseDiagnosis of idiopathic Parkinson's diseaseCorticobasal degenerationProgressive supranuclear palsyParkinson's diseaseMultiple system atrophyParkinsonSPECT protocol
2009
Quantitative simultaneous cardiac SPECT using MC‐JOSEM
Ouyang J, Zhu X, Trott C, Fakhri G. Quantitative simultaneous cardiac SPECT using MC‐JOSEM. Medical Physics 2009, 36: 602-611. PMID: 19292000, PMCID: PMC2673670, DOI: 10.1118/1.3063544.Peer-Reviewed Original ResearchConceptsMC-JOSEMEnergy windowWater-filled torso phantomScatter correctionPhotopeak energy windowStandard OSEMCardiac SPECT imagingActivity concentration ratioIterative reconstruction algorithmReconstruction algorithmMyocardium wallTorso phantomActivity estimationDetector responseEmission energyBackground compartmentPhantom dataCardiac SPECTActivity distributionRest/stress imagingScatteringCases of patientsOSEMChest painCardiac protocols
2008
Improved activity estimation with MC‐JOSEM versus TEW‐JOSEM in SPECT
Ouyang J, Fakhri G, Moore S. Improved activity estimation with MC‐JOSEM versus TEW‐JOSEM in SPECT. Medical Physics 2008, 35: 2029-2040. PMID: 18561679, PMCID: PMC2673642, DOI: 10.1118/1.2907561.Peer-Reviewed Original ResearchMeSH KeywordsAlgorithmsEquipment DesignImage Processing, Computer-AssistedIndium RadioisotopesLungModels, StatisticalMonte Carlo MethodPhantoms, ImagingRadiotherapy Planning, Computer-AssistedReproducibility of ResultsScattering, RadiationSoftwareTomography, Emission-Computed, Single-PhotonTomography, X-Ray ComputedConceptsMC-JOSEMWater-filled torso phantomMC scatter estimationTriple-energy-windowActivity estimationIterative reconstruction algorithmTorso phantomPhantom studyBackground compartmentScatter estimationActivity distributionAverage relative biasPhantomReconstruction algorithmActivity concentrationsSynthetic projectionsSphere locationScattering
2007
Fast Monte Carlo based joint iterative reconstruction for simultaneous SPECT imaging
Ouyang J, Fakhri G, Moore S. Fast Monte Carlo based joint iterative reconstruction for simultaneous SPECT imaging. Medical Physics 2007, 34: 3263-3272. PMID: 17879789, DOI: 10.1118/1.2756601.Peer-Reviewed Original ResearchConceptsMC-JOSEMEnergy windowFast Monte CarloSignal-to-noise ratioScatter correction methodOrdered-subsets expectation-maximizationMonte CarloOrdered-subsets expectation-maximization algorithmIterative reconstruction algorithmPrimary photonsReconstruction algorithmPhoton transportSeptal penetrationDetector responseMC simulationsIterative reconstructionAttenuation distributionStandard OSEMPhotonsProjection dataPatient-specific activityDetectorReconstructed imagesScatteringEstimation of scattering
2006
Generalized five‐dimensional dynamic and spectral factor analysis
Fakhri G, Sitek A, Zimmerman R, Ouyang J. Generalized five‐dimensional dynamic and spectral factor analysis. Medical Physics 2006, 33: 1016-1024. PMID: 16696478, DOI: 10.1118/1.2179168.Peer-Reviewed Original Research