2024
Subject-aware PET Denoising with Contrastive Adversarial Domain Generalization
Liu X, Marin T, Eslahi S, Tiss A, Chemli Y, Johson K, Fakhri G, Ouyang J. Subject-aware PET Denoising with Contrastive Adversarial Domain Generalization. 2011 IEEE Nuclear Science Symposium Conference Record 2024, 00: 1-1. PMID: 39445307, PMCID: PMC11497478, DOI: 10.1109/nss/mic/rtsd57108.2024.10656150.Peer-Reviewed Original ResearchDomain generalizationDenoising performanceDenoising moduleDeep learningSubject-independent mannerSubject-invariant featuresSuperior denoising performanceAdversarial learning frameworkSubject-related informationConventional UNetBottleneck featuresTrustworthy systemsLearning frameworkDL modelsDL model performanceDenoisingNoise realizationsNegative samplesList-mode dataImage volumesModel performancePerformancePerformance of positron emission tomographyUNetFraction of eventsCross noise level PET denoising with continuous adversarial domain generalization
Liu X, Eslahi S, Marin T, Tiss A, Chemli Y, Huang Y, Johnson K, Fakhri G, Ouyang J. Cross noise level PET denoising with continuous adversarial domain generalization. Physics In Medicine And Biology 2024, 69: 085001. PMID: 38484401, PMCID: PMC11195012, DOI: 10.1088/1361-6560/ad341a.Peer-Reviewed Original ResearchDomain generalization techniqueDomain generalizationDenoising performanceSuperior denoising performanceLatent feature representationGeneral techniqueDistribution shiftsAdversarial trainingDenoised imageFeature representationDomain labelsDistribution divergenceNoise levelDeep learningImage spaceDenoisingPerformance degradationCore ideaNoise realizationsCD methodNoiseImage volumesPerformanceImagesPSNR
2018
MR-based motion correction for cardiac PET parametric imaging: a simulation study
Guo R, Petibon Y, Ma Y, El Fakhri G, Ying K, Ouyang J. MR-based motion correction for cardiac PET parametric imaging: a simulation study. EJNMMI Physics 2018, 5: 3. PMID: 29388075, PMCID: PMC5792384, DOI: 10.1186/s40658-017-0200-9.Peer-Reviewed Original ResearchNon-motion-correctedPositron emission tomography-magnetic resonanceMR-based motion correctionRespiratory motionMotion correctionActivity distributionMotion correction methodRespiratory gatingPET sinogramsNoise levelCardiac gatingMRI simulationOne-tissue compartment modelNoise realizationsMC methodPET dataCardiac motionReduce motion blurParametric imagesIncreased noise levelConclusionsThis simulation studyArterial input functionPET imagingGateMyocardial regions
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
2014
MR‐based motion correction for PET imaging using wired active MR microcoils in simultaneous PET‐MR: Phantom study
Huang C, Ackerman J, Petibon Y, Brady T, Fakhri G, Ouyang J. MR‐based motion correction for PET imaging using wired active MR microcoils in simultaneous PET‐MR: Phantom study. Medical Physics 2014, 41: 041910. PMID: 24694141, PMCID: PMC3978416, DOI: 10.1118/1.4868457.Peer-Reviewed Original ResearchConceptsMotion correctionMR-based motion correctionStatic phantom dataPET quantitative accuracyPET-MRPET-MR scannersSimultaneous PET-MRHoffman phantomList-modePositron emission tomography imagingPET reconstructionBrain positron emission tomographyIterative PET reconstructionPhantom dataPhantomQuantitative accuracyIndependent noise realizationsImage contrastNoise realizationsHead motionPET dataPositron emission tomographyStatic referenceBrain PET scansMotion artifactsMotion 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 noise
2003
Quantitative Ga-67 SPECT Imaging
Moore S, Fakhri G, Park I, Kijewski M. Quantitative Ga-67 SPECT Imaging. 2003, 4: 2898-2900. DOI: 10.1109/nssmic.2003.1352489.Peer-Reviewed Original ResearchPb X-raysContaminating photonsPatient scatterUnscattered photonsAnthropomorphic phantomPhotopeak windowNonuniform attenuationCollimator resolutionAttenuation mapGa-67Iterative reconstructionProjection imagesTumor activityPhotonsNoise realizationsGa-67 imagingTumor estimationQuantitative imagingHistopathological stagingLocal backgroundTumor avidityAverage precisionX-rayCollimatorIterative algorithm
2001
Realistic Monte Carlo Simulation of Ga-67 SPECT Imaging
Moore S, El Fakhri G. Realistic Monte Carlo Simulation of Ga-67 SPECT Imaging. IEEE Transactions On Nuclear Science 2001, 48: 720. DOI: 10.1109/23.940153.Peer-Reviewed Original ResearchRealistic Monte Carlo simulationsNumerical torso phantomLead X-raysMonte Carlo programPhoton emission energyPoisson noise realizationsGa-67 SPECT imagingCollimator penetrationDetector resolutionEnergy windowRSD phantomPhoton propagationPhoton scatteringTorso phantomHeart/thorax phantomAttenuation mapEnergy distributionEmission energyImproved variance reductionSPECT imagesPhantomGa-67 studiesNoise realizationsScatteringAxillary lymph nodesA New Scatter Compensation Method for Ga-67 Imaging Using Artificial Neural Networks
Fakhri G, Moore S, Maksud P. A New Scatter Compensation Method for Ga-67 Imaging Using Artificial Neural Networks. IEEE Transactions On Nuclear Science 2001, 48: 799. DOI: 10.1109/23.940166.Peer-Reviewed Original ResearchK-shell X-raysEnergy window imagesAnthropomorphic torso phantomPoisson noise realizationsGa-67 studiesArtificial neural networkWindow imagesPhotoelectric absorptionPhoton interactionsTorso phantomCoherent scatteringMonte Carlo simulationsScatter correctionGa-67Neural networkReconstructed volumeCarlo simulationsCollimatorArtificial neural network learningError back propagationNoise realizationsScatteringGa-67 imagingActivity estimationOutput layerComparative Assessment of Energy-Based Methods of Compensating for Scatter and Lead X-Rays in Ga-67 SPECT Imaging
Moore S, Fakhri G, Maksud P. Comparative Assessment of Energy-Based Methods of Compensating for Scatter and Lead X-Rays in Ga-67 SPECT Imaging. 2001, 4: 2197-2198. DOI: 10.1109/nssmic.2001.1009260.Peer-Reviewed Original ResearchLead X-raysGa-67Energy windowArtificial neural networkGa-67 SPECT imagingSPECT imagesHigh-energy contaminationGa-67 SPECTPoisson noise realizationsActivity estimation taskTumor activity concentrationAnthropomorphic phantomEvaluable tumorsGS methodTumorMean square errorData setsOrgan uptakeProjection imagesLymphoma studiesNeural networkPixel valuesX-raySpherical tumorNoise realizations
2000
A new scatter compensation method for Ga-67 imaging using artificial neural networks
Fakhri G, Moore S, Maksud P. A new scatter compensation method for Ga-67 imaging using artificial neural networks. 2011 IEEE Nuclear Science Symposium Conference Record 2000, 2: 13/48-13/52 vol.2. DOI: 10.1109/nssmic.2000.949989.Peer-Reviewed Original ResearchK-shell X-raysEnergy window imagesAnthropomorphic torso phantomScatter correction methodPoisson noise realizationsGa-67 studiesPhotoelectric absorptionPhoton interactionsWindow imagesTorso phantomArtificial neural networkCoherent scatteringMonte Carlo simulationsScatter correctionGa-67Reconstructed volumeNeural networkCarlo simulationsCollimatorNoise realizationsScatteringGa-67 imagingArtificial neural network learningPrimary distributionError backpropagationRealistic Monte Carlo simulation of Ga-67 imaging for optimization and evaluation of correction methods
Moore S, Fakhri G. Realistic Monte Carlo simulation of Ga-67 imaging for optimization and evaluation of correction methods. 2011 IEEE Nuclear Science Symposium Conference Record 2000, 3: 20/35-20/38 vol.3. DOI: 10.1109/nssmic.2000.949312.Peer-Reviewed Original ResearchRealistic Monte Carlo simulationsNumerical torso phantomMonte Carlo programLead X-raysPhoton emission energyPoisson noise realizationsMaximum rectangular regionCollimator penetrationDetector resolutionEnergy windowRSD phantomPhoton scatteringPhoton propagationTorso phantomHeart/thorax phantomAttenuation mapEnergy distributionEmission energyImproved variance reductionPhantomNoise-free imageGa-67 studiesGa-67Noise realizationsScattering