2016
Impact of motion and partial volume effects correction on PET myocardial perfusion imaging using simultaneous PET-MR
Petibon Y, Guehl N, Reese T, Ebrahimi B, Normandin M, Shoup T, Alpert N, Fakhri G, Ouyang J. Impact of motion and partial volume effects correction on PET myocardial perfusion imaging using simultaneous PET-MR. Physics In Medicine And Biology 2016, 62: 326-343. PMID: 27997375, PMCID: PMC5241952, DOI: 10.1088/1361-6560/aa5087.Peer-Reviewed Original ResearchConceptsSimultaneous PET-MRPET myocardial perfusion imagingMyocardial perfusion imagingPoint spread functionPoint-spread function correctionUngated dataMotion correctionPET-MRPartial volume effectsApparent wall thicknessMyocardial blood flowPartial volume effect correctionMR-based motion correctionMotion fieldPET-MR scannersPoint spread function modelPET dataPerfusion imagingImage qualityImpact of motionDynamic myocardial perfusion imagingAttenuation mapNon-rigid registrationAbsolute myocardial blood flowUngated images
2015
Pulmonary imaging using respiratory motion compensated simultaneous PET/MR
Dutta J, Huang C, Li Q, Fakhri G. Pulmonary imaging using respiratory motion compensated simultaneous PET/MR. Medical Physics 2015, 42: 4227-4240. PMID: 26133621, PMCID: PMC4474958, DOI: 10.1118/1.4921616.Peer-Reviewed Original ResearchConceptsRespiratory motionContrast-to-noise ratioClinical patient studiesPulse sequenceHigh-intensity featuresXCAT studyLow proton densityXCAT simulationPatient studiesXCAT phantomAttenuation mapBiograph mMRComplete data acquisitionSimultaneous PET/MRNonrigid registrationPET/MR scannersPET/magnetic resonanceMagnetic susceptibilityProton densityQuantitative accuracyRelaxation timePulmonary imagingLung lesionsBlurring artifactsDeformation field
2014
Accuracy of Respiratory Motion Compensated Image Reconstruction Using 4DPET-Derived Deformation Fields
Dutta J, Chelala M, Shao X, Lorsakul A, Li Q, Fakhri G. Accuracy of Respiratory Motion Compensated Image Reconstruction Using 4DPET-Derived Deformation Fields. 2014, 1-4. DOI: 10.1109/nssmic.2014.7430924.Peer-Reviewed Original ResearchAttenuation-corrected PET imagesXCAT phantomNon-attenuation-corrected PET imagesMotion-compensated image reconstructionImage reconstructionMotion informationPET imagingMotion estimationPET gatingAttenuation mapBreathing motionPET quantitationSoftware GATEXCATDeformation fieldPhantomAccuracy of motionGround truthGateAnatomical imagesFieldMotionUpper abdomenPulmonary lesionsMonteTowards 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
2013
Bias Atlases for Segmentation-Based PET Attenuation Correction Using PET-CT and MR
Ouyang J, Chun Y, Petibon Y, Bonab A, Alpert N, Fakhri G. Bias Atlases for Segmentation-Based PET Attenuation Correction Using PET-CT and MR. IEEE Transactions On Nuclear Science 2013, 60: 3373-3382. PMID: 24966415, PMCID: PMC4067048, DOI: 10.1109/tns.2013.2278624.Peer-Reviewed Original ResearchAttenuation correctionBias imagesLung density variationsPET attenuation correctionPET-MR scannersAttenuation mapFat identificationOriginal CTPET reconstructionOverall standard deviationPET-MRMR imagingVariation of biasDensity variationsCT-based studyPET accuracyPET-CTStandard deviation of biasCorrectionFat segmentationTissue classesPatientsSoft tissueAttenuationLungRESPIRATORY MOTION COMPENSATION IN SIMULTANEOUS PET/MR USING A MAXIMUM A POSTERIORI APPROACH
Dutta J, Fakhri G, Huang C, Petibon Y, Reese T, Li Q. RESPIRATORY MOTION COMPENSATION IN SIMULTANEOUS PET/MR USING A MAXIMUM A POSTERIORI APPROACH. 2013, 800-803. DOI: 10.1109/isbi.2013.6556596.Peer-Reviewed Original ResearchGated MR imagesSimultaneous PET/MRRespiratory motion compensationPulse sequencePET image reconstructionBiograph mMR scannerEstimation of deformation fieldsReference gateRespiratory motionAttenuation mapTime binsPET reconstructionWhole-body PET/MR imagingAnatomical MR imagesMotion artifactsPET/MR dataNon-rigid registrationFLASH pulse sequenceSacrificing image qualityPET/MR imagingImage reconstructionGateSimultaneous acquisitionMaximum-a-posteriori approachDeformation field
2011
Nonrigid PET motion compensation in the lower abdomen using simultaneous tagged‐MRI and PET imaging
Guérin B, Cho S, Chun S, Zhu X, Alpert N, Fakhri G, Reese T, Catana C. Nonrigid PET motion compensation in the lower abdomen using simultaneous tagged‐MRI and PET imaging. Medical Physics 2011, 38: 3025-3038. PMID: 21815376, PMCID: PMC3125080, DOI: 10.1118/1.3589136.Peer-Reviewed Original ResearchConceptsPET-MRI acquisitionsMotion correctionPET motion compensationPET motion correctionRespiratory motion correctionMotion-corrected reconstructionMotion correction strategiesWhole-body PET studiesSignal-to-noise ratioPET reconstruction algorithmDeformable phantomNCAT phantomEffects of motionAttenuation mapDetected coincidencesPET-MRIGated framesBrain scannerSimulations of tumorsSignal-to-noisePhantomSusceptibility artifactsReconstruction algorithmPhase domainsNonrigid deformation
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 ResearchConceptsAttenuation-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 improvementFBPScattering
2004
Quantitative SPECT leads to improved performance in discrimination tasks related to prodromal Alzheimer's disease.
El Fakhri G, Kijewski M, Albert M, Johnson K, Moore S. Quantitative SPECT leads to improved performance in discrimination tasks related to prodromal Alzheimer's disease. Journal Of Nuclear Medicine 2004, 45: 2026-31. PMID: 15585477.Peer-Reviewed Original ResearchConceptsProdromal Alzheimer's diseaseMemory problemsAlzheimer's diseaseDiagnosis of prodromal Alzheimer's diseaseDiagnosis of prodromal ADClinical tasksMRI volume estimationsVariable collimator responseFollow-up periodDementiaGeneral spectral methodConverter groupFollow-upProdromal ADUniform attenuation mapQuestion groupsPairwise discriminant analysisSubjectsQuantitative approachDiscrimination accuracyAnterior cingulate gyrusAttenuation mapNonuniform attenuation mapNormal groupCingulate gyrus
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
2002
Impact of Acquisition Geometry and Patient Habitus on Lesion Detectability in Whole-Body FDG-PET: A Channelized Hotelling Observer Study
Fakhri G, Holdsworth C, Badawi R, Santos P, Moore S, Van den Abbeele A, Kijewski M. Impact of Acquisition Geometry and Patient Habitus on Lesion Detectability in Whole-Body FDG-PET: A Channelized Hotelling Observer Study. 2002, 3: 1402-1405. DOI: 10.1109/nssmic.2002.1239583.Peer-Reviewed Original ResearchBed positionChannelized Hotelling observer studyFDG-PET studiesAttenuation mapAcquisition modeMarginal detectionFDG-PETLesion detectionWhole-body FDG-PETHotelling observerScaling 2DTypical sizePatient sizeHours post-injectionPatient habitusAnatomical backgroundWhole bodyLesion sizeObservational studyPatientsLesionsLesion siteModePost-injectionAcquisition geometry
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 nodes
2000
Realistic 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