2023
PET image denoising based on denoising diffusion probabilistic model
Gong K, Johnson K, El Fakhri G, Li Q, Pan T. PET image denoising based on denoising diffusion probabilistic model. European Journal Of Nuclear Medicine And Molecular Imaging 2023, 51: 358-368. PMID: 37787849, PMCID: PMC10958486, DOI: 10.1007/s00259-023-06417-8.Peer-Reviewed Original ResearchMeSH KeywordsAlgorithmsHumansImage Processing, Computer-AssistedModels, StatisticalPositron-Emission TomographySignal-To-Noise RatioConceptsDenoising diffusion probabilistic modelPET image denoisingDiffusion probabilistic modelImage denoisingDenoising methodNonlocal meansNetwork inputGenerative adversarial networkData consistency constraintsProbabilistic modelLearning-based modelsAdversarial networkData distributionDenoisingRefinement stepsIterative refinementFlexible frameworkImage qualityPhysical degrading factorsUNetNetworkDatasetImagesInputNoise level
2020
A Radio-Nano-Platform for T1/T2 Dual-Mode PET-MR Imaging
Gholami Y, Yuan H, Wilks M, Maschmeyer R, Normandin M, Josephson L, Fakhri G, Kuncic Z. A Radio-Nano-Platform for T1/T2 Dual-Mode PET-MR Imaging. International Journal Of Nanomedicine 2020, 15: 1253-1266. PMID: 32161456, PMCID: PMC7049573, DOI: 10.2147/ijn.s241971.Peer-Reviewed Original ResearchConceptsLine spread functionPET-MR imagingSignal-to-noise ratioFull-width half-maximum (FWHMPET-MRHalf-maximum (FWHMSpatial resolutionTransmission electron microscopyImage quality gainSimultaneous positron emission tomographyContrast-enhanced diagnostic imagingAtom adsorptionPhantom imagesPositron emission tomographySpatial resolution of MRHybrid PET-MRRadio-isotopesSpread functionMulti-modal imaging techniquesSensitivity of positron emission tomographyMagnetic resonanceCo-registeredTransmission electron microscopy analysisSuper paramagnetic iron oxide nanoparticlesContrast agents
2019
Arterial spin labeling MR image denoising and reconstruction using unsupervised deep learning
Gong K, Han P, Fakhri G, Ma C, Li Q. Arterial spin labeling MR image denoising and reconstruction using unsupervised deep learning. NMR In Biomedicine 2019, 35: e4224. PMID: 31865615, PMCID: PMC7306418, DOI: 10.1002/nbm.4224.Peer-Reviewed Original ResearchMeSH KeywordsBrainDeep LearningHumansImage Processing, Computer-AssistedMagnetic Resonance ImagingSignal-To-Noise RatioSpin LabelsConceptsSignal-to-noise ratioImage denoisingReconstruction frameworkDeep learning-based image denoisingDeep learning-based denoisersMR image denoisingLearning-based denoisingLow signal-to-noise ratioK-space dataNoisy imagesTraining labelsTraining pairsNetwork inputNeural networkDenoisingIn vivo experiment dataSuperior performanceImaging speedReconstruction processImage qualityLong imaging timesNetworkFrameworkImagesSpatial resolution
2018
Joint reconstruction of rest/stress myocardial perfusion SPECT
Lai X, Petibon Y, Fakhri G, Ouyang J. Joint reconstruction of rest/stress myocardial perfusion SPECT. Physics In Medicine And Biology 2018, 63: 135019. PMID: 29897044, PMCID: PMC6245543, DOI: 10.1088/1361-6560/aacc2f.Peer-Reviewed Original ResearchConceptsMyocardial perfusion imagingSingle photon emission computed tomographyReversible defectsSignal-to-noise ratioRest/stress SPECT myocardial perfusion imagingSPECT myocardial perfusion imagingConventional subtraction methodDefect detectionJoint methodPhoton emission computed tomographySubtraction methodReverse mappingClinical dose levelsEmission computed tomographyImprove defect detectionLow noiseNon-invasive assessmentClinical dosePerfusion defectsReduced doseImprove radiologists' performanceReconstruction frameworkRest imagesPerfusion imagingDose levels
2017
Joint reconstruction of Ictal/inter‐ictal SPECT data for improved epileptic foci localization
Rakvongthai Y, Fahey F, Borvorntanajanya K, Tepmongkol S, Vutrapongwatana U, Zukotynski K, Fakhri G, Ouyang J. Joint reconstruction of Ictal/inter‐ictal SPECT data for improved epileptic foci localization. Medical Physics 2017, 44: 1437-1444. PMID: 28211105, PMCID: PMC5462456, DOI: 10.1002/mp.12167.Peer-Reviewed Original ResearchConceptsSPECT reconstruction methodDifferential imagingLow-noise datasetConventional subtraction methodLesion contrastSPECT projection dataEpileptic focus localizationHoffman phantomPatient studiesReconstruction methodJoint methodSPECT projectionsHead phantomPhantom locationsSubtraction methodPhantom studyNuclear medicine physiciansAttenuation backgroundPhantomConventional subtraction approachFocus localizationConventional subtractionReceiver operating characteristicLow noiseProjection dataDirect 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
A novel approach to assess the treatment response using Gaussian random field in PET
Wang M, Guo N, Hu G, El Fakhri G, Zhang H, Li Q. A novel approach to assess the treatment response using Gaussian random field in PET. Medical Physics 2016, 43: 833-842. PMID: 26843244, PMCID: PMC4714995, DOI: 10.1118/1.4939879.Peer-Reviewed Original ResearchMeSH KeywordsImage Processing, Computer-AssistedMonte Carlo MethodNormal DistributionPositron-Emission TomographyPrecision MedicineSignal-To-Noise RatioTreatment OutcomeConceptsTherapy response assessmentStandardized uptake valuePositron emission tomographyEarly treatment responseResponse assessmentPositron emission tomography imagingTreatment responseTherapy responsePrediction of early treatment responseTreatment planningResponse to anticancer therapyTherapy response evaluationTumor-to-background contrastPost-therapy imagingClinical practiceEvaluate therapy responseReceiver operating characteristic curveDevelopment of personalized treatment plansEvaluate therapy effectsPersonalized treatment plansUptake valuePretherapy imagingClinical oncologyPatient managementAnticancer therapy
2014
4D 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 approachMotion 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