2023
B1 inhomogeneity‐corrected T1 mapping and quantitative magnetization transfer imaging via simultaneously estimating Bloch‐Siegert shift and magnetization transfer effects
Jang A, Han P, Ma C, Fakhri G, Wang N, Samsonov A, Liu F. B1 inhomogeneity‐corrected T1 mapping and quantitative magnetization transfer imaging via simultaneously estimating Bloch‐Siegert shift and magnetization transfer effects. Magnetic Resonance In Medicine 2023, 90: 1859-1873. PMID: 37427533, PMCID: PMC10528411, DOI: 10.1002/mrm.29778.Peer-Reviewed Original ResearchConceptsBloch-Siegert shiftBloch-SiegertMagnetization transfer effectsMonte Carlo simulationsSpin-lattice relaxationSpin-bath modelMagnetization transferBinary spin-bath modelCarlo simulationsProton fractionOff-resonance irradiationIn vivo brain studiesBloch simulationsPhantom experimentsMagnetizationEstimationTransmitted fieldQuantitative magnetization transferMethod performanceMT effectSignal equation
2017
Use of Monte Carlo Techniques in Nuclear Medicine
Fahey F, Grogg K, Fakhri G. Use of Monte Carlo Techniques in Nuclear Medicine. Journal Of The American College Of Radiology 2017, 15: 446-448. PMID: 29173989, PMCID: PMC6335966, DOI: 10.1016/j.jacr.2017.09.045.Peer-Reviewed Original ResearchFeasibility study of using fall‐off gradients of early and late PET scans for proton range verification
Cho J, Grogg K, Min C, Zhu X, Paganetti H, Lee H, Fakhri G. Feasibility study of using fall‐off gradients of early and late PET scans for proton range verification. Medical Physics 2017, 44: 1734-1746. PMID: 28273345, PMCID: PMC5462437, DOI: 10.1002/mp.12191.Peer-Reviewed Original ResearchMeSH KeywordsFeasibility StudiesHumansMonte Carlo MethodPhantoms, ImagingPositron-Emission TomographyProtonsConceptsProton range verificationProton rangeMonte Carlo simulationsRange verificationFall-offIn-room positron emission tomographyCarlo simulationsResidual proton rangeDose fall-offPostirradiation delayPositron emission tomography imagingSOBP beamProton beamPositron emission tomographyPositron emission tomography scanPhantom studyIn-roomFunction of depthPhantomProtonOff-setMonteAcquisition timeBeamPositron emission tomography signal
2015
Monitoring proton therapy with PET
Paganetti H, Fakhri G. Monitoring proton therapy with PET. British Journal Of Radiology 2015, 88: 20150173. PMID: 25989699, PMCID: PMC4628541, DOI: 10.1259/bjr.20150173.Peer-Reviewed Original ResearchMapping 15O Production Rate for Proton Therapy Verification
Grogg K, Alpert N, Zhu X, Min C, Testa M, Winey B, Normandin M, Shih H, Paganetti H, Bortfeld T, Fakhri G. Mapping 15O Production Rate for Proton Therapy Verification. International Journal Of Radiation Oncology • Biology • Physics 2015, 92: 453-459. PMID: 25817530, PMCID: PMC4431894, DOI: 10.1016/j.ijrobp.2015.01.023.Peer-Reviewed Original ResearchConceptsDecay constantProton treatment planningMonte Carlo predictionsProton therapyPhantom materialTreatment deliveryPhantomThigh activityPositron emission tomographyProduction rateDynamic PET measurementsTreatment planningRabbit thigh muscleClearance rateProtonIsotopesChanges due to therapyRadionuclide speciesOxygen-15ConstantDecayImaging targetsMontePositronEffects of perfusion
2014
4D numerical observer for lesion detection in respiratory‐gated PET
Lorsakul A, Li Q, Trott C, Hoog C, Petibon Y, Ouyang J, Laine A, Fakhri G. 4D numerical observer for lesion detection in respiratory‐gated PET. Medical Physics 2014, 41: 102504. PMID: 25281979, PMCID: PMC4281099, DOI: 10.1118/1.4895975.Peer-Reviewed Original ResearchMeSH KeywordsAlgorithmsComputer SimulationFluorodeoxyglucose F18HumansImage Interpretation, Computer-AssistedLung DiseasesModels, BiologicalMonte Carlo MethodMotionPhantoms, ImagingPositron-Emission TomographyRadiopharmaceuticalsRegression AnalysisRespiratory-Gated Imaging TechniquesSignal-To-Noise RatioConceptsRespiratory-gated positron emission tomographyMotion-corrected imagesDetection signal-to-noise ratioLesion detection taskNumerical observationsLesion detection performanceSignal-to-noise ratioPositron emission tomography sinogramsSpherical lesionsHotelling observerMotion correction methodPositron emission tomographyGeant4 ApplicationTomographic EmissionChannelized Hotelling observerAnthropomorphic phantomScanner geometryOSEM algorithmMonte Carlo simulationsPET framesImprove lesion detectionLesion detectionSignal-to-noise ratio measurementsActivity distributionConventional 3D approach
2013
Simultaneous 99mTc‐MDP/123I‐MIBG tumor imaging using SPECT‐CT: Phantom and constructed patient studies
Rakvongthai Y, Fakhri G, Lim R, Bonab A, Ouyang J. Simultaneous 99mTc‐MDP/123I‐MIBG tumor imaging using SPECT‐CT: Phantom and constructed patient studies. Medical Physics 2013, 40: 102506. PMID: 24089927, PMCID: PMC3785531, DOI: 10.1118/1.4820977.Peer-Reviewed Original ResearchConceptsScatter correctionDual-radionuclideContrast recoveryPhantom studyAnthropomorphic torso phantomPatient studiesTumor uptakeTumor imagingSPECT projectionsTorso phantomMonte-CarloPhantom dataPhantomIterative reconstructionOSEMProjection dataDR dataIncrease patient throughputNoise realizationsSPECT-CTImage reconstructionClinical studiesTumorTumor projectionPoisson noiseClinical Application of In-Room Positron Emission Tomography for In Vivo Treatment Monitoring in Proton Radiation Therapy
Min C, Zhu X, Winey B, Grogg K, Testa M, Fakhri G, Bortfeld T, Paganetti H, Shih H. Clinical Application of In-Room Positron Emission Tomography for In Vivo Treatment Monitoring in Proton Radiation Therapy. International Journal Of Radiation Oncology • Biology • Physics 2013, 86: 183-189. PMID: 23391817, PMCID: PMC3640852, DOI: 10.1016/j.ijrobp.2012.12.010.Peer-Reviewed Original ResearchConceptsIn-room positron emission tomographyProton therapyIn-roomPositron emission tomography scanIn-room PET scannerPassive scattering proton therapyShapes of target volumesPositron emission tomographyMC predictionBeam range uncertaintiesMeasured PET imagesMonte CarloProton radiation therapyLocal elemental compositionBiological washoutScan timeTreatment headTreatment verificationRange uncertaintiesTarget volumePET scan timePET scannerPET systemComputed tomographyMC results
2011
Monitoring proton radiation therapy with in-room PET imaging
Zhu X, España S, Daartz J, Liebsch N, Ouyang J, Paganetti H, Bortfeld T, Fakhri G. Monitoring proton radiation therapy with in-room PET imaging. Physics In Medicine And Biology 2011, 56: 4041-4057. PMID: 21677366, PMCID: PMC3141290, DOI: 10.1088/0031-9155/56/13/019.Peer-Reviewed Original ResearchConceptsIn-room positron emission tomographyIn-roomProton therapy treatment roomPositron emission tomography systemProton range verificationSoft tissue-equivalent materialMonte Carlo predictionsTissue-equivalent materialsPositron emission tomography acquisition timesProton radiation therapyPositron emission tomographyBiological washoutRange verificationProton therapyList-modeActivity distribution patternsPhantom studyTreatment roomPET acquisitionSoft tissue regionsIn vivo verificationDeep-siteOff-line modalityPositron emission tomography dataAdenoid cystic carcinoma
2010
Dual-Radionuclide Brain SPECT for the Differential Diagnosis of Parkinsonism
El Fakhri G, Ouyang J. Dual-Radionuclide Brain SPECT for the Differential Diagnosis of Parkinsonism. Methods In Molecular Biology 2010, 680: 237-246. PMID: 21153385, DOI: 10.1007/978-1-60761-901-7_16.Peer-Reviewed Original ResearchConceptsDopamine transporter functionBrain SPECTDifferential diagnosis of parkinsonismDifferential diagnosisDiagnosis of parkinsonismIdiopathic Parkinson's diseaseDifferential diagnosis of idiopathic Parkinson’s diseaseDiagnosis of idiopathic Parkinson's diseaseCorticobasal degenerationProgressive supranuclear palsyParkinson's diseaseMultiple system atrophyParkinsonSPECT protocol
2009
Quantitative simultaneous cardiac SPECT using MC‐JOSEM
Ouyang J, Zhu X, Trott C, Fakhri G. Quantitative simultaneous cardiac SPECT using MC‐JOSEM. Medical Physics 2009, 36: 602-611. PMID: 19292000, PMCID: PMC2673670, DOI: 10.1118/1.3063544.Peer-Reviewed Original ResearchConceptsMC-JOSEMEnergy windowWater-filled torso phantomScatter correctionPhotopeak energy windowStandard OSEMCardiac SPECT imagingActivity concentration ratioIterative reconstruction algorithmReconstruction algorithmMyocardium wallTorso phantomActivity estimationDetector responseEmission energyBackground compartmentPhantom dataCardiac SPECTActivity distributionRest/stress imagingScatteringCases of patientsOSEMChest painCardiac protocols
2008
Improved 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
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
2001
Absolute activity quantitation in simultaneous 123I/99mTc brain SPECT.
El Fakhri G, Moore S, Maksud P, Aurengo A, Kijewski M. Absolute activity quantitation in simultaneous 123I/99mTc brain SPECT. Journal Of Nuclear Medicine 2001, 42: 300-8. PMID: 11216530.Peer-Reviewed Original ResearchAlzheimer DiseaseBenzamidesBrainCerebellumCerebral CortexCerebrovascular CirculationCorpus CallosumHumansIodine RadioisotopesMonte Carlo MethodNeural Networks, ComputerParkinson DiseasePhantoms, ImagingPutamenPyrrolidinesRadiopharmaceuticalsSensitivity and SpecificityTechnetium Tc 99m ExametazimeTomography, Emission-Computed, Single-Photon
1998
Artificial neural network as a tool to compensate for scatter and attenuation in radionuclide imaging.
Maksud P, Fertil B, Rica C, El Fakhri G, Aurengo A. Artificial neural network as a tool to compensate for scatter and attenuation in radionuclide imaging. Journal Of Nuclear Medicine 1998, 39: 735-45. PMID: 9544691.Peer-Reviewed Original Research