2021
A layered single-side readout depth of interaction time-of-flight-PET detector
Bläckberg L, Sajedi S, Fakhri G, Sabet H. A layered single-side readout depth of interaction time-of-flight-PET detector. Physics In Medicine And Biology 2021, 66: 045025. PMID: 33570050, PMCID: PMC8130834, DOI: 10.1088/1361-6560/abd592.Peer-Reviewed Original ResearchConceptsDepth of interactionMulti-pixel photon counterDepth-of-interaction determinationDepth-of-interaction informationTime resolutionTime resolution valuesReduced crystal thicknessNon-DOI detectorsOptical photonsScintillator arrayPET detectorsPhoton counterCrystal pixelsReadout schemeCrystal arrayCrystal thicknessTransport simulationsDetectorPhotodetector arrayReadoutPixel sizePhotodetectorsResolution valuesFirst layerSignal amplitude
2017
Simulation study of light transport in laser-processed LYSO:Ce detectors with single-side readout
Bläckberg L, Fakhri G, Sabet H. Simulation study of light transport in laser-processed LYSO:Ce detectors with single-side readout. Physics In Medicine And Biology 2017, 62: 8419-8440. PMID: 29047453, PMCID: PMC5736368, DOI: 10.1088/1361-6560/aa8dea.Peer-Reviewed Original ResearchMeSH KeywordsCerium RadioisotopesComputer SimulationEquipment DesignLasersLightPhotonsScintillation CountingConceptsDetector typesLYSO:Ce detectorsLYSO:Ce crystalsBarrier refractive indexScintillation light transportImproved energy resolutionRefractive indexLaser-processed crystalsCollection efficiencyLight transportPixel-like patternScintillation lightMPPC arraysEnergy resolutionPixel arrayDOI informationPulsed laser beamLight response functionLine profilesCe crystalsMonolithic crystalsBarrier patternsCrystal bulkTime resolutionCE detector
2016
Novel laser‐processed CsI:Tl detector for SPECT
Sabet H, Bläckberg L, Uzun-Ozsahin D, El-Fakhri G. Novel laser‐processed CsI:Tl detector for SPECT. Medical Physics 2016, 43: 2630-2638. PMID: 27147372, PMCID: PMC5148208, DOI: 10.1118/1.4947294.Peer-Reviewed Original ResearchConceptsOptical barrierPeak-to-valley (P/VCsI:Tl crystalsCrystal bulkMultipixel photon counterPixel-like patternScintillation lightEnergy resolutionKeV gammasPixelated scintillatorScintillator samplesPhoton counterTL detectorsTl crystalsFabricated detectorScintillationCrystal thicknessSpatial resolutionPixel arrayDetectorBarrier patternsFabricated arraysCSICrystalBulk
2014
Myocardial Defect Detection Using PET-CT: Phantom Studies
Mananga E, Fakhri G, Schaefferkoetter J, Bonab A, Ouyang J. Myocardial Defect Detection Using PET-CT: Phantom Studies. PLOS ONE 2014, 9: e88200. PMID: 24505429, PMCID: PMC3914931, DOI: 10.1371/journal.pone.0088200.Peer-Reviewed Original ResearchMeSH KeywordsAlgorithmsEquipment DesignFemaleHumansMaleMyocardiumPhantoms, ImagingPositron-Emission TomographyConceptsMyocardial defect detectionFiltered back projectionChannelized Hotelling observerPhantom studyActivity distributionSubset expectation maximizationDefect detectionCardiac PET studiesMyocardial defectsHotelling observerNoise levelBack-projectionPET-CTPhantomExpectation maximizationOP-OSEMReconstruction schemePET studiesOSEMDefectsNoise
2008
Sequential and simultaneous dual‐isotope brain SPECT: Comparison with PET for estimation and discrimination tasks in early Parkinson disease
Trott C, Fakhri G. Sequential and simultaneous dual‐isotope brain SPECT: Comparison with PET for estimation and discrimination tasks in early Parkinson disease. Medical Physics 2008, 35: 3343-3353. PMID: 18697558, PMCID: PMC2673561, DOI: 10.1118/1.2940605.Peer-Reviewed Original ResearchConceptsEnergy resolutionTime-of-flight PET scannerRealistic Monte Carlo simulationsAcquisition energy windowSequential SPECTSystem energy resolutionGamma cameraEnergy windowThree-head cameraPET scannerEmission energyMonte Carlo simulationsDual-isotope SPECTSimultaneous SPECTBrain PETTwo-headed cameraCarlo simulationsProdromal disease stagesIdentical physiological conditionsSpatial resolutionDiscrimination taskStriatal sizeActivity concentrationsEarly identification of PDCamera headImproved activity estimation with MC‐JOSEM versus TEW‐JOSEM in SPECT
Ouyang J, Fakhri G, Moore S. Improved activity estimation with MC‐JOSEM versus TEW‐JOSEM in SPECT. Medical Physics 2008, 35: 2029-2040. PMID: 18561679, PMCID: PMC2673642, DOI: 10.1118/1.2907561.Peer-Reviewed Original ResearchMeSH KeywordsAlgorithmsEquipment DesignImage Processing, Computer-AssistedIndium RadioisotopesLungModels, StatisticalMonte Carlo MethodPhantoms, ImagingRadiotherapy Planning, Computer-AssistedReproducibility of ResultsScattering, RadiationSoftwareTomography, Emission-Computed, Single-PhotonTomography, X-Ray ComputedConceptsMC-JOSEMWater-filled torso phantomMC scatter estimationTriple-energy-windowActivity estimationIterative reconstruction algorithmTorso phantomPhantom studyBackground compartmentScatter estimationActivity distributionAverage relative biasPhantomReconstruction algorithmActivity concentrationsSynthetic projectionsSphere locationScattering
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 activityCollimator Optimization for Detection and Quantitation Tasks: Application to Gallium-67 Imaging
Moore S, Kijewski M, Fakhri G. Collimator Optimization for Detection and Quantitation Tasks: Application to Gallium-67 Imaging. IEEE Transactions On Medical Imaging 2005, 24: 1347-1356. PMID: 16229420, DOI: 10.1109/tmi.2005.857211.Peer-Reviewed Original ResearchMeSH KeywordsCitratesComputer SimulationComputer-Aided DesignEquipment DesignEquipment Failure AnalysisGalliumHumansImage EnhancementImage Interpretation, Computer-AssistedModels, BiologicalNeoplasmsPhantoms, ImagingPositron-Emission TomographyRadiopharmaceuticalsReproducibility of ResultsSensitivity and SpecificityConceptsMedium-energy low-penetration collimatorCollimator optimizationGeometric spatial resolutionPhotopeak energy windowSimulation of photon transportLead X-raysClinical imaging tasksActivity estimation taskSignal-to-noise ratioGallium-67 imagingContaminating photonsEnergy windowGeometric efficiencyCollimator designFixed energyPhoton transportOptimal collimatorCollimatorHotelling observerFWHMSpatial resolutionNuclear medicineDetectorResolution valuesImaging tasks