2024
PET motion correction using subspace-based real-time MR imaging in simultaneous PET/MR
Mounime I, Marin T, Han P, Ouyang J, Gori P, Angelini E, Fakhri G, Ma C. PET motion correction using subspace-based real-time MR imaging in simultaneous PET/MR. 2024, 00: 1-1. DOI: 10.1109/nss/mic/rtsd57108.2024.10657647.Peer-Reviewed Original ResearchOrdered-subset expectation maximizationMotion correctionGated reconstructionsMotion-corrected PET reconstructionsPET eventsCardiac motion phasesMotion correction methodCardiac motionMotion phaseReconstructed dynamic imagesPET reconstructionReal-time MR imagingSimultaneous PET/MRPatient motionSoft tissue contrastDynamic MR image reconstructionReference phaseMitigate artifactsLow-rank propertyMR image reconstructionPositron emission tomographyManifold learning frameworkSpatial resolutionBlurring artifactsImage reconstructionFlat Panel TOF-PET Detectors: a Simulation Study
Orehar M, Dolenec R, Fakhri G, Gascón D, Gola A, Korpar S, Križan P, Razdevšek G, Marin T, Chemli Y, Žontar D, Pestotnik R. Flat Panel TOF-PET Detectors: a Simulation Study. 2024, 00: 1-2. DOI: 10.1109/nss/mic/rtsd57108.2024.10658250.Peer-Reviewed Original ResearchTime resolutionAngular coverageFlat-panel detectorScintillation materialsGATE softwareAxial coverageBiograph VisionPanel detectorTotal-body coverageClinical scannerImage reconstructionDetectorReconstructed imagesHomogeneous contrastCylindrical scannerImage qualityState-of-the-artScintillationHigh-performance computingScannerPhantomResolutionCore hoursPositron emission tomographyGateDIANA - Detectability Investgations using Artificial Nodal Additions
Bayerlein R, Xia M, Xie H, Spencer B, Ouyang J, Fakhri G, Nardo L, Liu C, Badawi R. DIANA - Detectability Investgations using Artificial Nodal Additions. 2024, 00: 1-1. DOI: 10.1109/nss/mic/rtsd57108.2024.10657528.Peer-Reviewed Original ResearchContrast recovery coefficientContrast-to-noise ratioLesion-to-background ratioList-mode dataTotal-body PET/CT scannerPositron emission tomographyContrast recoveryOSEM algorithmPatient motionPET/CT scannerArtificial lesionsImage quality metricsLesion detectionQuantitative accuracyPositron emission tomography scanRecovery coefficientCount densityImage contrastBody mass indexImage noisePositron emission tomography imaging techniquesFrame lengthImage smoothingActivity concentrationsAccuracy of lesion detectionEffects of List-Mode-Based Intraframe Motion Correction in Dynamic Brain PET Imaging
Tiss A, Chemli Y, Guehl N, Marin T, Johnson K, Fakhri G, Ouyang J. Effects of List-Mode-Based Intraframe Motion Correction in Dynamic Brain PET Imaging. IEEE Transactions On Radiation And Plasma Medical Sciences 2024, 8: 950-958. PMID: 39507127, PMCID: PMC11540417, DOI: 10.1109/trpms.2024.3432322.Peer-Reviewed Original ResearchAssociations of cerebral amyloid beta and tau with cognition from midlife
Gonzales M, O'Donnell A, Ghosh S, Thibault E, Tanner J, Satizabal C, Decarli C, Fakhri G, Johnson K, Beiser A, Seshadri S, Pase M. Associations of cerebral amyloid beta and tau with cognition from midlife. Alzheimer's & Dementia 2024, 20: 5901-5911. PMID: 39039896, PMCID: PMC11497641, DOI: 10.1002/alz.14060.Peer-Reviewed Original ResearchApolipoprotein E e4Associated with cognitionTau positron emission tomographyPositron emission tomographyWorsening cognitionCommunity-based cohortYoung adultsApolipoprotein EStudy investigated associationsPoor visuospatial skillsDementia preventionTargeted early interventionE4 statusCerebral amyloid-betaEffect modifiersHigher amyloidAPOE e4 carriersCognitive vulnerabilityAssociation of amyloidVisuospatial skillsResilience factorsEarly interventionYounger ageCognitionE4 carriersAdvances and Insights in Positron Emission Tomography Tracers for Metabotropic Glutamate Receptor 4 Imaging
Wang J, Li Y, Fakhri G. Advances and Insights in Positron Emission Tomography Tracers for Metabotropic Glutamate Receptor 4 Imaging. Journal Of Medicinal Chemistry 2024, 67: 10517-10529. PMID: 38924702, PMCID: PMC11290609, DOI: 10.1021/acs.jmedchem.3c02431.Peer-Reviewed Original ResearchConceptsPositive allosteric modulatorsPositron emission tomographyPositron emission tomography radioligandsAllosteric modulatorsMGluR4 positive allosteric modulatorsMetabotropic glutamate receptor subtype 4PET ligandNeurological disordersPositron emission tomography tracersEmission tomographySubtype 4Molecular imaging modalitiesEffective treatmentMetabotropicDisordersParent drugImaging modalitiesPET tracersMGluR4Therapeutic targetPositron emitting radioisotopesSelection of lead compoundsLiving subjectsPositronQuantitative accuracyPET imaging of M4 muscarinic acetylcholine receptors in rhesus macaques using [11C]MK-6884: Quantification with kinetic modeling and receptor occupancy by CVL-231 (emraclidine), a novel positive allosteric modulator
Belov V, Guehl N, Duvvuri S, Iredale P, Moon S, Dhaynaut M, Chakilam S, MacDonagh A, Rice P, Yokell D, Renger J, Fakhri G, Normandin M. PET imaging of M4 muscarinic acetylcholine receptors in rhesus macaques using [11C]MK-6884: Quantification with kinetic modeling and receptor occupancy by CVL-231 (emraclidine), a novel positive allosteric modulator. Cerebrovascular And Brain Metabolism Reviews 2024, 44: 1329-1342. PMID: 38477292, PMCID: PMC11342722, DOI: 10.1177/0271678x241238820.Peer-Reviewed Original ResearchConceptsPositive allosteric modulatorsReceptor occupancyNon-human primatesBinding potentialPositron emission tomographyMuscarinic acetylcholine receptorsAllosteric modulatorsNon-human primate brainM4 muscarinic acetylcholine receptorStriatal hyperdopaminergiaAcetylcholine receptorsBrain regionsCaudate nucleusTotal volume of distributionDose-dependent blockReference regionVolume of distributionPositron emission tomography imagingEmission tomographyReceptor levelsFunction of dosePET scansClinical trialsBlood-basedRhesus macaques
2023
Locus coeruleus metabolic changes as a predictor of tau accumulation and cognitive decline
Koops E, Dutta J, Becker A, Van Egroo M, Riphagen J, Hanseeuw B, Sperling R, Fakhri G, Johnson K, Jacobs H. Locus coeruleus metabolic changes as a predictor of tau accumulation and cognitive decline. Alzheimer's & Dementia 2023, 19 DOI: 10.1002/alz.073715.Peer-Reviewed Original ResearchBeta-amyloidTau pathologyAlzheimer's diseaseNeuropathological hallmarks of Alzheimer's diseaseHallmarks of Alzheimer's diseaseP-tauBeta-amyloid levelsP-tau accumulationMetabolic turnoverAccumulation of p-tauMarkers of AD progressionTau formationLocus coeruleusAD pathological changesTau accumulationNeuropathological hallmarksAD progressionPhosphorylated-tauPositron emission tomographyLate stageLociPairwise analysisMetabolismPair-wise differencesFDG-PET signalSimulation results for limited-angle ultra-high time-of-flight resolution PET system
Marin T, Zhuo Y, Orehar M, Razdevšekc G, Dolenec R, Mounime I, Alamo J, Benlloch J, Chemli Y, Fernández-Tenllado J, Gascon D, Gola A, Gomez S, Grogg K, Guberman D, Korpar S, Krizan P, Majewski S, Manera R, Mariscal-Castilla A, Mauricio J, Merzi S, Morera C, Normandin M, Pavon G, Penna M, Seljak A, Studen A, Pestotnik R, Fakhri G. Simulation results for limited-angle ultra-high time-of-flight resolution PET system. 2023, 00: 1-1. DOI: 10.1109/nssmicrtsd49126.2023.10337821.Peer-Reviewed Original ResearchResolution PET systemsPET systemAxial fieldPositron emission tomography systemPositron emission tomography scannerTotal-body PET systemsLong axial fieldTOF resolutionNovel detectorNumerical phantomHigh-sensitivity systemMonte-Carlo simulationsSpatial resolutionPositron emission tomographyMonte-CarloSystem sensitivityImage resolutionImage qualityScintillationReconstruction engineFWHMResolutionTOFPhantomScannerTau-PET abnormality as a biomarker for Alzheimer’s disease staging and early detection: a topological perspective
Ding J, Shen C, Wang Z, Yang Y, Fakhri G, Lu J, Liang D, Zheng H, Zhou Y, Sun T, Study F. Tau-PET abnormality as a biomarker for Alzheimer’s disease staging and early detection: a topological perspective. Cerebral Cortex 2023, 33: 10649-10659. PMID: 37653600, DOI: 10.1093/cercor/bhad312.Peer-Reviewed Original ResearchConceptsStandardized uptake value ratioMild cognitive impairmentBrain regionsCognitive impairmentPositron emission tomographyMedial temporal lobeAlzheimer's diseaseVisual-related regionsTopological perspectiveTau positron emission tomographyMode networkTau PET imagingTopological featuresIndependent data cohortsTemporal lobeConnection strengthExtract topological featuresTau networksAbnormal networkProgression of Alzheimer's diseaseAbnormal protein accumulationLongitudinal Imaging in a Patient With Opioid-associated Amnestic Syndrome
Barash J, Schmahmann J, Xie Z, Lev M, Fakhri G. Longitudinal Imaging in a Patient With Opioid-associated Amnestic Syndrome. Cognitive And Behavioral Neurology 2023, 36: 194-197. PMID: 37389894, PMCID: PMC10527331, DOI: 10.1097/wnn.0000000000000347.Peer-Reviewed Original ResearchConceptsOpioid-associated amnestic syndromeFluid-attenuated inversion recoveryPositron emission tomographyAmnestic syndromeHistory of attention-deficit hyperactivity disorderAttention-deficit hyperactivity disorderBrain regions of individualsSubstance use disordersOpioid misuseMild memory lossN-acetyl aspartate/creatineUrine toxicology screenFollow-up imagingHistory of opioid misuseRegions of individualsTau depositionTau positron emission tomographyHyperactivity disorderIntravenous heroinRight hippocampusAnterograde amnesiaRestricted diffusionBrain regionsHippocampal abnormalitiesLongitudinal imagingTau Positron Emission Tomography and Neurocognitive Function Among Former Professional American-Style Football Players
Dhaynaut M, Grashow R, Normandin M, Wu O, Marengi D, Terry D, Sanchez J, Weisskopf M, Speizer F, Taylor H, Guehl N, Seshadri S, Beiser A, Daneshvar D, Johnson K, Iverson G, Zafonte R, Fakhri G, Baggish A. Tau Positron Emission Tomography and Neurocognitive Function Among Former Professional American-Style Football Players. Journal Of Neurotrauma 2023, 40: 1614-1624. PMID: 37282582, PMCID: PMC10458363, DOI: 10.1089/neu.2022.0454.Peer-Reviewed Original ResearchConceptsPositron emission tomographyDistribution volume ratioNeuropsychological testsNeurocognitive functionStandardized uptake value ratioControl participantsMeasures of neurocognitive functionStructural magnetic resonance imagingMeasures of memoryDepressive symptom severityMale control participantsEmission tomographyCerebellar gray matterNeuropsychological measuresTau positron emission tomographyExecutive functionSymptom severityBrain regionsEntorhinal cortexRepetitive head impactsP-tauReference regionFormer playersRepetitive head impact exposureMale controlsFully automated radiosynthesis of [18F]mG4P027 for mGluR4 imaging
Moon S, Fakhri G, Zhang Z, Brownell A, Wang J. Fully automated radiosynthesis of [18F]mG4P027 for mGluR4 imaging. IRADIOLOGY 2023, 1: 120-127. PMID: 37496513, PMCID: PMC10371389, DOI: 10.1002/ird3.25.Peer-Reviewed Original ResearchImpact of motion correction on [18F]-MK6240 tau PET imaging
Tiss A, Marin T, Chemli Y, Spangler-Bickell M, Gong K, Lois C, Petibon Y, Landes V, Grogg K, Normandin M, Becker A, Thibault E, Johnson K, Fakhri G, Ouyang J. Impact of motion correction on [18F]-MK6240 tau PET imaging. Physics In Medicine And Biology 2023, 68: 105015. PMID: 37116511, PMCID: PMC10278956, DOI: 10.1088/1361-6560/acd161.Peer-Reviewed Original ResearchConceptsMotion correctionPET quantitationImpact of motion correctionList-mode reconstructionMotion correction methodList-mode dataMotion-corrected imagesEffect of motion correctionVoxel displacementsPhantom experimentsOptical tracking dataLong acquisitionBrain PET scansSlow motionImage qualityPET imagingPositron emission tomographyCorrectionMotionCorrection methodRates of tau accumulationHead motionMotion metricsPhantomPositronSuper-resolution in brain positron emission tomography using a real-time motion capture system
Chemli Y, Tétrault M, Marin T, Normandin M, Bloch I, El Fakhri G, Ouyang J, Petibon Y. Super-resolution in brain positron emission tomography using a real-time motion capture system. NeuroImage 2023, 272: 120056. PMID: 36977452, PMCID: PMC10122782, DOI: 10.1016/j.neuroimage.2023.120056.Peer-Reviewed Original ResearchConceptsBrain positron emission tomographySuper-resolutionEvent-by-event basisReal-time motion capture systemSR reconstruction methodTracking cameraVisualization of small structuresPET reconstruction algorithmMoving phantomMeasure target motionLine profilesPET/CT scannerMeasured shiftsImprove image resolutionMotion capture systemMotion tracking devicePositron emission tomographyReconstruction algorithmSpatial resolutionMeasured linesPhantomReal-timeEstimation frameworkIncreased spatial resolutionReconstruction method
2022
Simulation study of a 50 ps panel TOF PET imager
Pestotnik R, Razdevšek G, Dolenec R, Fakhri G, Križan P, Majewski S, Studen A, Korpar S. Simulation study of a 50 ps panel TOF PET imager. Journal Of Instrumentation 2022, 17: c12010. DOI: 10.1088/1748-0221/17/12/c12010.Peer-Reviewed Original ResearchPET scannerGamma detectorGamma raysTime-of-flight positron emission tomographyState-of-the-art clinical PET scannersGamma detection efficiencyClinical PET scannerImaging large objectsImproved time resolutionArtifact-free imagesDifferent phantomsDetector arrangementTime-of-flightBiograph VisionImage quality parametersDetection efficiencyTiming accuracyTime resolutionDetectorFWHMPositron emission tomographyReconstructed imagesRaysPositron emission tomography imagingMultichannel systemRadiochemical Synthesis and Evaluation of 3‑[11C]Methyl-4-aminopyridine in Rodents and Nonhuman Primates for Imaging Potassium Channels in the CNS
Sun Y, Guehl N, Zhou Y, Takahashi K, Belov V, Dhaynaut M, Moon S, Fakhri G, Normandin M, Brugarolas P. Radiochemical Synthesis and Evaluation of 3‑[11C]Methyl-4-aminopyridine in Rodents and Nonhuman Primates for Imaging Potassium Channels in the CNS. ACS Chemical Neuroscience 2022, 13: 3342-3351. PMID: 36417797, PMCID: PMC9732819, DOI: 10.1021/acschemneuro.2c00364.Peer-Reviewed Original ResearchConceptsRegional brain time-activity curvesBrain time-activity curvesOne-tissue compartment modelBlood-brain barrierConsistent with <i>inNonhuman primatesTime-activity curvesPositron emission tomographySpinal cord injuryDemyelinated neuronsNeurological symptomsPotassium channelsNeuronal conductionBrain uptakeEmission tomographyStille cross-couplingMultiple sclerosisCord injurySlow kineticsBrain permeabilityTraumatic brainMyelin sheathStronger binding affinityNeuronsBrainOptimization of Design Parameters of Flat Panel Limited Angle TOF-PET Scanner: a Simulation Study
Orehar M, Dolenec R, Fakhri G, Gascón D, Gola A, Korpar S, Križan P, Razdevšek G, Pestotnik R. Optimization of Design Parameters of Flat Panel Limited Angle TOF-PET Scanner: a Simulation Study. 2022, 00: 1-4. DOI: 10.1109/nss/mic44845.2022.10399330.Peer-Reviewed Original ResearchImage quality phantomFlat-panel detectorGATE softwareRing scannerPanel detectorDetection chainState-of-the-artNEMA standardsOpen geometryImage reconstructionReconstructed imagesPositron emission tomographyState-of-the-art scannersScannerPhantomDetectorPhotodetectorsElectronNEMAMaterial costGatePositronPET imaging studies to investigate functional expression of mGluR2 using [11C]mG2P001
Yuan G, Dhaynaut M, Guehl N, Neelamegam R, Moon S, Qu X, Poutiainen P, Afshar S, Fakhri G, Normandin M, Brownell A. PET imaging studies to investigate functional expression of mGluR2 using [11C]mG2P001. Cerebrovascular And Brain Metabolism Reviews 2022, 43: 296-308. PMID: 36172629, PMCID: PMC9903221, DOI: 10.1177/0271678x221130387.Peer-Reviewed Original ResearchConceptsPositive allosteric modulatorsPositron emission tomographyNon-human primatesMGluR2 positive allosteric modulatorPositron emission tomography imagingPositive allosteric modulator of mGluR2Metabotropic glutamate receptor 2Positron emission tomography imaging studiesExpression of mGluR2Glutamate receptor 2MGluR2 functionPsychiatric disordersMGluR2 expressionTissue glutamate concentrationMGluR2Expressing mGluR2Allosteric modulatorsRat brainTransfected CHO cellsReceptor 2Glutamate concentrationEmission tomographyImaging studiesPharmacological effectsImaging ligandsSynthesis and Characterization of 5‑(2-Fluoro-4‑[11C]methoxyphenyl)-2,2-dimethyl-3,4-dihydro‑2H‑pyrano[2,3‑b]pyridine-7-carboxamide as a PET Imaging Ligand for Metabotropic Glutamate Receptor 2
Yuan G, Dhaynaut M, Lan Y, Guehl N, Huynh D, Iyengar S, Afshar S, Jain M, Pickett J, Kang H, Wang H, Moon S, Ondrechen M, Wang C, Shoup T, Fakhri G, Normandin M, Brownell A. Synthesis and Characterization of 5‑(2-Fluoro-4‑[11C]methoxyphenyl)-2,2-dimethyl-3,4-dihydro‑2H‑pyrano[2,3‑b]pyridine-7-carboxamide as a PET Imaging Ligand for Metabotropic Glutamate Receptor 2. Journal Of Medicinal Chemistry 2022, 65: 2593-2609. PMID: 35089713, PMCID: PMC9434702, DOI: 10.1021/acs.jmedchem.1c02004.Peer-Reviewed Original ResearchConceptsNegative allosteric modulatorsMetabotropic glutamate receptor 2Positron emission tomographyGlutamate receptor 2MGluR2 functionNeuropsychiatric disordersDrug effectsBrain heterogeneityReceptor 2Allosteric modulatorsMGluR2Nonhuman primatesBrain imagingPositron emission tomography imagingPositron emission tomography imaging ligandsHigh molar activityEmission tomographyExcellent radiochemical purityImaging ligandsBlocking agentsPET imagingMolar activityTherapeutic targetMetabotropicDisorders