2024
Integration of a continuously varying image-space PSF for a dual-panel ultra-high TOF-PET scanner
Chemli Y, Marin T, Orehar M, Dolenec R, Normandin M, Gascón D, Gola A, Grogg K, Pavón G, Razdevsek G, Pestotnik R, Fakhri G. Integration of a continuously varying image-space PSF for a dual-panel ultra-high TOF-PET scanner. 2024, 00: 1-1. DOI: 10.1109/nss/mic/rtsd57108.2024.10656225.Peer-Reviewed Original ResearchGaussian mixture modelGaussian process regressionPoint spread functionAccurate image reconstructionMaximum likelihood estimation maximizationShift-variant convolutionsImage reconstructionMixture modelProcess regressionEstimation maximizationTime-of-flight (TOFPanel architectureSpread functionArchitectureParameter interpolationHigh resolution time-of-flight (TOFTOF-PET scannerBrain phantomFitting processPositron emission tomography scannerSimulated point sourcesConvolutionAlgorithmEffective diagnosisSize benefits
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 imagesGATE Simulation of a High-Performance Stationary SPECT System for Cardiac Imaging
Uzun-Özşahin D, Bläckberg L, Moghadam N, Fakhri G, Sabet H. GATE Simulation of a High-Performance Stationary SPECT System for Cardiac Imaging. 2016, 1-3. DOI: 10.1109/nssmic.2016.8069814.Peer-Reviewed Original ResearchPoint spread functionDerenzo-like phantomGATE simulated resultsGATE simulation studiesSystem spatial resolutionStationary SPECT systemGATE simulationsSPECT systemMultiple simultaneous viewsCardiac imaging applicationsActive rodsSpread functionSpatial resolutionImaging applicationsImage reconstructionGateCorrection techniqueFWHMContouring systemPhantomResolutionLaserCardiac imaging
2014
Quantitative simultaneous positron emission tomography and magnetic resonance imaging
Ouyang J, Petibon Y, Huang C, Reese T, Kolnick A, Fakhri G. Quantitative simultaneous positron emission tomography and magnetic resonance imaging. Journal Of Medical Imaging 2014, 1: 033502-033502. PMID: 26158055, PMCID: PMC4306197, DOI: 10.1117/1.jmi.1.3.033502.Peer-Reviewed Original ResearchEffect of time‐of‐flight and point spread function modeling on detectability of myocardial defects in PET
Schaefferkoetter J, Ouyang J, Rakvongthai Y, Nappi C, El Fakhri G. Effect of time‐of‐flight and point spread function modeling on detectability of myocardial defects in PET. Medical Physics 2014, 41: 062502. PMID: 24877836, PMCID: PMC4032408, DOI: 10.1118/1.4875725.Peer-Reviewed Original ResearchConceptsSignal-to-noise ratioDetection signal-to-noise ratioPoint spread functionObserver signal-to-noise ratioEffects of time-of-flightMyocardial defectsHuman observer performanceDefect detectionSlow convergenceTime-of-flight (TOFNon-PSFPostreconstruction smoothingFDG-PET dataTime-of-flightPSF reconstructionCombination of TOFNon-TOFIterationObserver performanceClinical practiceSpread functionReconstruction parametersReconstruction protocolsIterative methodDetectionRelative 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 correction
2013
Cardiac motion compensation and resolution modeling in simultaneous PET-MR: a cardiac lesion detection study
Petibon Y, Ouyang J, Zhu X, Huang C, Reese T, Chun S, Li Q, Fakhri G. Cardiac motion compensation and resolution modeling in simultaneous PET-MR: a cardiac lesion detection study. Physics In Medicine And Biology 2013, 58: 2085-2102. PMID: 23470288, PMCID: PMC3657754, DOI: 10.1088/0031-9155/58/7/2085.Peer-Reviewed Original ResearchConceptsContrast recoveryDetector point spread functionPartial volume effectsK-spaceMotion compensationB-spline registrationLesion-detection studiesCardiac motion compensationPET-MR scannersSimultaneous PET-MRPET contrastIterative reconstruction frameworkPoint spread functionMotion correctionPET countsNon-rigid B-spline registrationCardiac phantomPSF modelPET-MRMotion deblurringReconstruction frameworkSystem matrixCardiac PETSpread functionDefect detectionClinical impact of time-of-flight and point response modeling in PET reconstructions: a lesion detection study
Schaefferkoetter J, Casey M, Townsend D, Fakhri G. Clinical impact of time-of-flight and point response modeling in PET reconstructions: a lesion detection study. Physics In Medicine And Biology 2013, 58: 1465-1478. PMID: 23403399, PMCID: PMC3616316, DOI: 10.1088/0031-9155/58/5/1465.Peer-Reviewed Original ResearchConceptsPoint spread functionTime-of-flightBenefit of TOFPET reconstructionNumerical modelOptimal reconstruction parametersLocalization receiver operating characteristicsLesion-detection studiesObserved SNRReconstruction schemeSpread functionReconstruction parametersPerformanceNumerical observationsPatient images
2006
Monte Carlo-based compensation for patient scatter, detector scatter, and crosstalk contamination in In-111 SPECT imaging
Moore S, Ouyang J, Park M, Fakhri G. Monte Carlo-based compensation for patient scatter, detector scatter, and crosstalk contamination in In-111 SPECT imaging. Nuclear Instruments And Methods In Physics Research Section A Accelerators Spectrometers Detectors And Associated Equipment 2006, 569: 472-476. DOI: 10.1016/j.nima.2006.08.079.Peer-Reviewed Original ResearchScatter projectionsPatient scatterDetector scatterOrgan activity estimatesPhoton interaction pointIterative reconstruction algorithmDetector effectsEnergy binsReconstruction algorithmDelta scatteringTorso phantomPoint spread functionSegmented CT scanInteraction pointOSEM reconstructionNumerical phantomDetectorScatteringScattering mapSpherical tumorSpread functionImage noisePhantomActivity concentrationsActivity estimation
2005
Performance of a novel collimator for high‐sensitivity brain SPECT
Fakhri G, Ouyang J, Zimmerman R, Fischman A, Kijewski M. Performance of a novel collimator for high‐sensitivity brain SPECT. Medical Physics 2005, 33: 209-215. PMID: 16485427, DOI: 10.1118/1.2143140.Peer-Reviewed Original ResearchConceptsSphere activity concentrationNPW-SNRStandard collimatorSphere-to-background activity ratiosAttenuation of countsPhantom centerActivity concentrationsPoint spread functionCentral regionCollimatorPhantom studyStriatal phantomCylindrical backgroundResolution recoveryPhantomSpherical lesionsRamp filterCrystal surfaceSpread functionSignal-to-noise ratioCentral brain structuresFitting imageHealthy volunteersBrain SPECTSphere activity