2010
Novel Scatter Compensation of List-Mode PET Data Using Spatial and Energy Dependent Corrections
Guérin B, Fakhri G. Novel Scatter Compensation of List-Mode PET Data Using Spatial and Energy Dependent Corrections. IEEE Transactions On Medical Imaging 2010, 30: 759-773. PMID: 21118770, PMCID: PMC3120772, DOI: 10.1109/tmi.2010.2095025.Peer-Reviewed Original ResearchConceptsScattered coincidencesEnergy resolutionE-pdfNCAT phantomDependent correctionsEnergy of individual photonsScatter correctionEnergy dependent correctionsEnergy probability density functionScatter correction schemeTotal energy spectrumList-mode acquisitionEnergy informationPositron emission tomography dataActivity distribution estimationScatter sinogramIndividual photonsEnergy spectrumCylindrical phantomEnergy distributionMonte Carlo simulationsScattering approachPhotonsScatteringScattering component
2009
Monte Carlo modeling of cascade gamma rays in 86Y PET imaging: preliminary results
Zhu X, Fakhri G. Monte Carlo modeling of cascade gamma rays in 86Y PET imaging: preliminary results. Physics In Medicine And Biology 2009, 54: 4181-4193. PMID: 19521011, PMCID: PMC3111055, DOI: 10.1088/0031-9155/54/13/014.Peer-Reviewed Original ResearchConceptsCascade gamma raysScatter fractionGamma raysPhoton energy distributionLow count ratesHigh-energy photonsMonte Carlo programScatter correction methodGATE simulation packageMonte Carlo modelDevelopment of correction methodsSpatial resolutionGamma photonsEnergy windowCount rateScattering eventsRandom coincidencesEnergy distributionPhantom acquisitionsPersonal dosimetryPET imagingVariance reduction techniquesPhotonsCorrection methodSimSET
2007
Fast 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
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
2004
A general-spectral method for improved quantitative SPECT imaging of indium-111
Moore S, Park M, Fakhri G, Gerbaudo V, Zimmerman R. A general-spectral method for improved quantitative SPECT imaging of indium-111. 2004, 6: 3682-3684. DOI: 10.1109/nssmic.2004.1466680.Peer-Reviewed Original ResearchRadiotherapy treatment planningList-mode dataFree of scatterQuantitative SPECT imagingScatter compensation methodsList-mode acquisitionDown-scatterScattered photonsPhoton scatteringPhotopeakQuantitative SPECTOSEM reconstructionSPECT imagesLeastsquares procedureDose specificationAttenuation projectionNoisy projectionsScatteringTreatment planningSphere activitySphere locationIndium-111PhotonsContrast valuesSphere position
2003
The Effects of Compensation for Scatter, Lead X-Rays, and High-Energy Contamination on Tumor Detectability and Activity Estimation in Ga-67 Imaging
Fakhri G, Kijewski M, Maksud P, Moore S. The Effects of Compensation for Scatter, Lead X-Rays, and High-Energy Contamination on Tumor Detectability and Activity Estimation in Ga-67 Imaging. IEEE Transactions On Nuclear Science 2003, 50: 439. DOI: 10.1109/tns.2003.812446.Peer-Reviewed Original ResearchLead X-raysHigh-energy contaminationPresence of scatteringOptimal energy windowSignal-to-noise ratioAnthropomorphic torso phantomHigh-energy photonsMonte Carlo programGa-67 imagingSpherical tumorCompton scatteringPhoton interactionsEnergy windowScattered photonsEnergy photonsPhotopeak windowTorso phantomActivity estimationHigh energyFactors affecting image qualityX-rayScatter correctionPhotopeakGa-67PhotonsQuantitative 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
2000
Scatter and cross-talk corrections in simultaneous Tc-99m/I-123 brain SPECT using constrained factor analysis and artificial neural networks
Fakhri G, Maksud P, Kijewski M, Haberi M, Todd-Pokropek A, Aurengo A, Moore S. Scatter and cross-talk corrections in simultaneous Tc-99m/I-123 brain SPECT using constrained factor analysis and artificial neural networks. IEEE Transactions On Nuclear Science 2000, 47: 1573-1580. DOI: 10.1109/23.873018.Peer-Reviewed Original ResearchSpectral factor analysisTc-99mEnergy window methodDigital brain phantomCross-talk correctionI-123 imagingUnscattered photonsTc-99m activityBrain phantomMonte Carlo simulationsI-123Dual-isotope studiesPhotonsCarlo simulationsTc-99Simultaneous imagingAssessment of brain perfusionCross-talkBrain structuresBrain SPECTArtificial neural networkBrain perfusionPhantomClinical potentialCaudate nucleus
1999
Monte Carlo evaluation of quantitation in simultaneous Tc-99m/I-123 brain SPECT using constrained spectral factor analysis
Fakhri G, Moore S, Kijewski M, Maksud P, Todd-Pokropek A. Monte Carlo evaluation of quantitation in simultaneous Tc-99m/I-123 brain SPECT using constrained spectral factor analysis. 2011 IEEE Nuclear Science Symposium Conference Record 1999, 3: 1392-1396 vol.3. DOI: 10.1109/nssmic.1999.842815.Peer-Reviewed Original ResearchSpectral factor analysisTc-99mEnergy window methodDigital brain phantomI-123 imagingUnscattered photonsTc-99m activityBrain phantomFiltered-backprojectionMonte Carlo simulationsPrimary spectraDual-isotope studiesI-123Monte Carlo evaluationPhotonsCarlo simulationsSimultaneous imagingMonteBrain structuresBrain SPECTTc-99PhantomCaudate nucleusSpectraPixel values