2020
Dynamic Cardiac SPECT for diagnostic and theranostics applications: latest results
Bläckberg L, Sajedi S, Anderson O, Feng Y, Fakhri G, Furenlid L, Sabet H. Dynamic Cardiac SPECT for diagnostic and theranostics applications: latest results. 2020, 00: 1-3. DOI: 10.1109/nss/mic42677.2020.9508002.Peer-Reviewed Original ResearchCsI:Tl crystalsMPPC arraysTl crystalsCsI:Tl scintillatorGamma-ray energiesCardiac SPECTCsI:TlLow energy resolutionCardiac SPECT imagingGamma cameraConventional gamma cameraResolution recovery techniquesSensL SiPMsEnergy resolutionStopping powerTl scintillatorDetector modulesReadout electronicsDynamic cardiac SPECTPinhole collimatorHigh power lasersPhantom studyCollimatorDetectorSiPM
2016
Development and characterization of a compact hand-held gamma probe system, SURGEOGUIDE, based on NEMA NU3-2004 standards
Kaviani S, Zeraatkar N, Sajedi S, Gorjizadeh N, Farahani M, Ghafarian P, Fakhri G, Sabet H, Ay M. Development and characterization of a compact hand-held gamma probe system, SURGEOGUIDE, based on NEMA NU3-2004 standards. Journal Of Instrumentation 2016, 11: t12004-t12004. DOI: 10.1088/1748-0221/11/12/t12004.Peer-Reviewed Original ResearchScattering mediumAngular resolutionCsI(Tl) scintillatorMeasured system sensitivitySingle-hole collimatorSpatial resolutionSilicon photomultipliersGamma probeDetector unitClinically node-negative patientsSentinel lymph node localizationTc-99mCollimatorNode-negative patientsSite of regional metastasisScatteringLymph node localizationIntra-operative gamma probePeritumoral injectionRegional metastasesNodal sitesPathological analysisProbe systemI-131NEMA
2006
Fast Monte Carlo Simulation Based Joint Iterative Reconstruction for Simultaneous 99mTc/123I Brain SPECT Imaging
Ouyang J, Fakhri G, Moore S, Kijewski M. Fast Monte Carlo Simulation Based Joint Iterative Reconstruction for Simultaneous 99mTc/123I Brain SPECT Imaging. 2006, 4: 2251-2256. DOI: 10.1109/nssmic.2006.354362.Peer-Reviewed Original ResearchMC-JOSEMAW-OSEMMonte CarloFast Monte CarloIterative reconstructionOrdered-subset expectation maximizationStandard ordered subsetsIterative reconstruction algorithmScattered photonsPhoton transportSeptal penetrationAttenuation distributionPhysical effectsIdentical physiological conditionsPatient-specific activityReconstructed imagesReconstruction algorithmActivity estimationComptonRoot mean square errorPhotonsCorrection methodCollimatorBrain perfusionDetector
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
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
Optimal Parallel-Hole Collimation for Lesion Detection and Activity Estimation in Ga-67 Imaging
Moore S, Kijewski M, Fakhri G. Optimal Parallel-Hole Collimation for Lesion Detection and Activity Estimation in Ga-67 Imaging. 2002, 3: 1390-1392. DOI: 10.1109/nssmic.2002.1239580.Peer-Reviewed Original ResearchCollimator designMedium-energy (MESimulation of photon transportSignal-to-noise ratioParallel-hole collimatorDesign of collimatorsClinical imaging tasksGa-67Contaminating photonsField of nuclear medicineEnergy windowFixed energyPhoton transportOptimal collimatorCollimatorCommercial collimatorsStaging of lymphoma patientsHotelling observerGa-67 imagingNuclear medicine clinicsLesion detectionNuclear medicineDetectorActivity concentrationsResolution values
2001
A New Scatter Compensation Method for Ga-67 Imaging Using Artificial Neural Networks
Fakhri G, Moore S, Maksud P. A New Scatter Compensation Method for Ga-67 Imaging Using Artificial Neural Networks. IEEE Transactions On Nuclear Science 2001, 48: 799. DOI: 10.1109/23.940166.Peer-Reviewed Original ResearchK-shell X-raysEnergy window imagesAnthropomorphic torso phantomPoisson noise realizationsGa-67 studiesArtificial neural networkWindow imagesPhotoelectric absorptionPhoton interactionsTorso phantomCoherent scatteringMonte Carlo simulationsScatter correctionGa-67Neural networkReconstructed volumeCarlo simulationsCollimatorArtificial neural network learningError back propagationNoise realizationsScatteringGa-67 imagingActivity estimationOutput layer
2000
A new scatter compensation method for Ga-67 imaging using artificial neural networks
Fakhri G, Moore S, Maksud P. A new scatter compensation method for Ga-67 imaging using artificial neural networks. 2011 IEEE Nuclear Science Symposium Conference Record 2000, 2: 13/48-13/52 vol.2. DOI: 10.1109/nssmic.2000.949989.Peer-Reviewed Original ResearchK-shell X-raysEnergy window imagesAnthropomorphic torso phantomScatter correction methodPoisson noise realizationsGa-67 studiesPhotoelectric absorptionPhoton interactionsWindow imagesTorso phantomArtificial neural networkCoherent scatteringMonte Carlo simulationsScatter correctionGa-67Reconstructed volumeNeural networkCarlo simulationsCollimatorNoise realizationsScatteringGa-67 imagingArtificial neural network learningPrimary distributionError backpropagation