2024
Accelerated 3D metabolite T1 mapping of the brain using variable‐flip‐angle SPICE
Zhao Y, Li Y, Guo R, Jin W, Sutton B, Ma C, Fakhri G, Li Y, Luo J, Liang Z. Accelerated 3D metabolite T1 mapping of the brain using variable‐flip‐angle SPICE. Magnetic Resonance In Medicine 2024, 92: 1310-1322. PMID: 38923032, DOI: 10.1002/mrm.30200.Peer-Reviewed Original ResearchConceptsLow-rank tensor modelGeneralized series modelMetabolite TExperimental resultsBrain metabolitesClinically acceptable scan timeEfficient encodingPhantom experimental resultsAcceptable scan timeNoisy dataSparse samplingImaging problemsData processingHealthy subject dataVariable flip angleFlip angleTensor modelSaturation effectsQuantitative metabolic imagingMRSI techniquePhantomScan timeData acquisitionMetabolic imagingT1 mapping
2023
Arterial spin labeled perfusion imaging with balanced steady-state free precession readout and radial sampling
Han P, Marin T, Zhuo Y, Ouyang J, El Fakhri G, Ma C. Arterial spin labeled perfusion imaging with balanced steady-state free precession readout and radial sampling. Magnetic Resonance Imaging 2023, 102: 126-132. PMID: 37187264, PMCID: PMC10524790, DOI: 10.1016/j.mri.2023.05.005.Peer-Reviewed Original ResearchMeSH KeywordsArteriesBrainImage Processing, Computer-AssistedImaging, Three-DimensionalMagnetic Resonance ImagingPerfusionPerfusion ImagingSpin LabelsConceptsOff-resonance effectsBalanced steady-state free precessionPhase-cycling techniqueTemporal SNRBalanced steady-state free precession acquisitionRadial sampling schemeSpoiled gradient-recalled acquisitionRadial samplingCartesian sampling schemeBalanced steady-state free precession readoutK-space dataSampling schemeSpin labelingSteady-state free precessionK-spaceImage readoutBanding artifactsMotion-related artifactsReadoutFree precessionArterial spin labelingImage reconstructionParallel imagingImaging timePerfusion-weighted imaging
2021
Quantitative PET in the 2020s: a roadmap
Meikle S, Sossi V, Roncali E, Cherry S, Banati R, Mankoff D, Jones T, James M, Sutcliffe J, Ouyang J, Petibon Y, Ma C, El Fakhri G, Surti S, Karp J, Badawi R, Yamaya T, Akamatsu G, Schramm G, Rezaei A, Nuyts J, Fulton R, Kyme A, Lois C, Sari H, Price J, Boellaard R, Jeraj R, Bailey D, Eslick E, Willowson K, Dutta J. Quantitative PET in the 2020s: a roadmap. Physics In Medicine And Biology 2021, 66: 06rm01. PMID: 33339012, PMCID: PMC9358699, DOI: 10.1088/1361-6560/abd4f7.Peer-Reviewed Original ResearchMeSH KeywordsArtificial IntelligenceHistory, 20th CenturyHistory, 21st CenturyHumansImage Processing, Computer-AssistedImaging, Three-DimensionalKineticsMedical OncologyNeoplasmsPositron Emission Tomography Computed TomographyPositron-Emission TomographyPrognosisRadiopharmaceuticalsSystems BiologyTomography, X-Ray ComputedConceptsTime-of-flight positron emission tomographyStatistical image reconstructionTotal-body positron emission tomographyPositron emission tomographyQuantitative positron emission tomographyImage reconstructionWhole-body positron emission tomographySensitivity of positron emission tomographyCapabilities of positron emission tomographyImage qualityClinical applicationTracer principleRelevant parametersOncology applicationsPhysicsStatistical qualityExpansion of applicationsEmission tomographyClinical practicePET/MRBiologically relevant parametersSensitive biomarkerPositron
2019
Free-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 ResearchMeSH KeywordsAlgorithmsHeartImage EnhancementImage Processing, Computer-AssistedImaging, Three-DimensionalMagnetic Resonance ImagingMyocardiumRespirationConceptsRespiratory 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
2015
Synergistic role of simultaneous PET/MRI-MRS in soft tissue sarcoma metabolism imaging
Zhang X, Chen Y, Lim R, Huang C, Chebib I, Fakhri G. Synergistic role of simultaneous PET/MRI-MRS in soft tissue sarcoma metabolism imaging. Magnetic Resonance Imaging 2015, 34: 276-279. PMID: 26523656, PMCID: PMC4761342, DOI: 10.1016/j.mri.2015.10.027.Peer-Reviewed Original ResearchConceptsSoft tissue sarcomasMagnetic resonance imagingHigh (18)F-FDG uptakeT2 hyperintense massMagnetic resonance spectroscopyNeoadjuvant radiotherapyPathological resultsTumor marginsTissue sarcomasImaging findingsPET/MRI scansPET scansRight thighRadiotherapyNormal tissuesEmission tomographyResonance imagingMetabolite profilesSarcomaPET/MRIChemoRTChemoradiationSynergistic rolePETSurgery
2014
Relative 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 correctionTowards coronary plaque imaging using simultaneous PET-MR: a simulation study
Petibon Y, Fakhri G, Nezafat R, Johnson N, Brady T, Ouyang J. Towards coronary plaque imaging using simultaneous PET-MR: a simulation study. Physics In Medicine And Biology 2014, 59: 1203-1222. PMID: 24556608, PMCID: PMC4061607, DOI: 10.1088/0031-9155/59/5/1203.Peer-Reviewed Original ResearchMeSH KeywordsComputer SimulationCoronary AngiographyCoronary StenosisHumansImage Interpretation, Computer-AssistedImaging, Three-DimensionalMagnetic Resonance AngiographyModels, CardiovascularMultimodal ImagingPhantoms, ImagingPositron-Emission TomographyReproducibility of ResultsSensitivity and SpecificityConceptsSimultaneous PET-MRChannelized Hotelling observerAttenuation mapMotion correctionPET-MRFluorodeoxyglucose-positron emission tomography imagingRespiratory motion fieldsMotion correction methodCho SNRMotion correction techniqueAnthropomorphic phantomUncorrected reconstructionsRespiratory motionXCAT phantomCoronary plaque imagingMonte Carlo simulationsPET reconstructionXCATActivity distributionCardiac gatingNon-rigid registrationHotelling observerCarlo simulationsPlaque imagingPhantom
2011
Improvement in Lesion Detection with Whole-Body Oncologic Time-of-Flight PET
Fakhri G, Surti S, Trott C, Scheuermann J, Karp J. Improvement in Lesion Detection with Whole-Body Oncologic Time-of-Flight PET. Journal Of Nuclear Medicine 2011, 52: 347-353. PMID: 21321265, PMCID: PMC3088884, DOI: 10.2967/jnumed.110.080382.Peer-Reviewed Original ResearchConceptsTime-of-flight PETTime-of-flightTOF-PETTime-of-flight reconstructionBody mass indexList-mode dataNon-TOF PETObserver signal-to-noise ratioOrdered-subset expectation maximizationMass indexNon-TOFLesion detectionLesion detection performanceSpherical lesionsFunction of body mass indexSignal-to-noise ratioScan timePatient studiesLesion visibilityArtificial lesionsLiver lesionsPatientsLesionsLesion locationLow lesions
2007
Impact of Acquisition Geometry, Image Processing, and Patient Size on Lesion Detection in Whole-Body 18F-FDG PET
Fakhri G, Santos P, Badawi R, Holdsworth C, Van Den Abbeele A, Kijewski M. Impact of Acquisition Geometry, Image Processing, and Patient Size on Lesion Detection in Whole-Body 18F-FDG PET. Journal Of Nuclear Medicine 2007, 48: 1951-1960. PMID: 18006613, DOI: 10.2967/jnumed.108.007369.Peer-Reviewed Original ResearchMeSH KeywordsBody Mass IndexFluorodeoxyglucose F18HumansImage Processing, Computer-AssistedImaging, Three-DimensionalNeoplasmsPositron-Emission TomographyRadiopharmaceuticalsWhole Body ImagingConceptsAttenuation-weighted OSEMOrdered-subset expectation maximizationNoise equivalent countPhantom sizeBed positionCho SNRPatient sizeFourier rebinningAttenuation mapPET scannerLesion detectionMarginal detectionTransmission scanWhole-body (18)F-FDG PETAttenuation correctionWhole-body 18F-FDG PETHotelling observerScaling 2DSinogramReconstructed volumeDetection SNRPhantomSystematic improvementFBPScatteringFast 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