Nicolas Guehl
Assistant Professor of Radiology and Biomedical ImagingCards
About
Research
Publications
2025
Quantifying extracerebral off‐target contamination in [18F]MK6240 PET imaging using compartmental modeling
Fu J, Lois C, Tiss A, Sari H, Becker A, Sanchez J, Guehl N, Normandin M, Fakhri G, Johnson K, Price J. Quantifying extracerebral off‐target contamination in [18F]MK6240 PET imaging using compartmental modeling. Alzheimer's & Dementia 2025, 21: e099911. PMCID: PMC12739924, DOI: 10.1002/alz70856_099911.Peer-Reviewed Original ResearchBayesian modelling applied to Tau PET to explore the effects of heterogeneity in tau patterns
Xia Y, Johnson K, Fakhri G, Guehl N, van de Giessen E, van der Flier W, Pijnenburg Y, Ossenkoppele R, Groot C. Bayesian modelling applied to Tau PET to explore the effects of heterogeneity in tau patterns. Alzheimer's & Dementia 2025, 21: e105595. PMCID: PMC12783061, DOI: 10.1002/alz70856_105595.Peer-Reviewed Original ResearchTau patternsFactor loadingsLate-onset ADAmsterdam Dementia CohortDistribution of factor loadingsTau heterogeneityBaseline cognitive performanceTau factorTau pathologyBaseline executive functionAmyloid-positive individualsDementia CohortLinear mixed effects analysisDiscovery cohortExecutive functionTauADNI participantsTau-PET patternsReplicate samplesTau-PETIndependent datasetsCognitive outcomesCognitive performanceSymptomatic ADPosterior factorsYRT-PET: An Open-Source GPU-Accelerated Image Reconstruction Engine for Positron Emission Tomography
Najmaoui Y, Chemli Y, Toussaint M, Petibon Y, Marty B, Fontaine K, Gallezot J, Razdevsek G, Orehar M, Dhaynaut M, Guehl N, Dolenec R, Pestotnik R, Johnson K, Ouyang J, Normandin M, Tetrault M, Lecomte R, Fakhri G, Marin T. YRT-PET: An Open-Source GPU-Accelerated Image Reconstruction Engine for Positron Emission Tomography. IEEE Transactions On Radiation And Plasma Medical Sciences 2025, PP: 1-1. PMID: 41424471, PMCID: PMC12714321, DOI: 10.1109/trpms.2025.3619872.Peer-Reviewed Original ResearchOpen-sourceImage reconstructionPositron emission tomography image reconstructionReconstruction algorithmAdvanced image reconstruction algorithmsOpen-source toolkitDevelopment of advanced algorithmsTime-of-flightScanner geometryNovel reconstruction algorithmImage reconstruction algorithmMotion correctionReusable codeGPU accelerationTime-of-flight informationPython bindingsPlugin systemSoftware toolkitMeaningful imagesData formatsFast implementationRigid motion correctionAdvanced algorithmsPoint spread function modelProprietary softwareBayesian Posterior Distribution Estimation of Kinetic Parameters in Dynamic Brain PET Using Generative Deep Learning Models
Djebra Y, Liu X, Marin T, Tiss A, Dhaynaut M, Guehl N, Johnson K, Fakhri G, Ma C, Ouyang J. Bayesian Posterior Distribution Estimation of Kinetic Parameters in Dynamic Brain PET Using Generative Deep Learning Models. IEEE Transactions On Medical Imaging 2025, 44: 5089-5102. PMID: 40663684, PMCID: PMC12318411, DOI: 10.1109/tmi.2025.3588859.Peer-Reviewed Original ResearchPosterior distributions of kinetic parametersEfficiency of deep learningGenerative deep learning modelsConditional variational autoencoderDeep learning modelsComputational efficiencyMetropolis-Hastings MCMCPosterior distributionHyperphosphorylated tauDynamic brain positron emission tomographyWGAN-GPDual decodersWasserstein GANVariational autoencoderKinetic parametersDeep learningComputational needsBayesian inferenceP-tauLearning modelsAlzheimer's diseaseNeurodegenerative diseasesComputation timeMCMC methodsEstimation of kinetic parametersQuantitative Measurement of Tau Burden in a Dual-Time-Window Dynamic PET Imaging Protocol with [18F]MK6240
Xia Y, Dhaynaut M, Chemli Y, Lois C, Hanseeuw B, Thibault E, Groot C, Ossenkoppele R, Johnson K, El Fakhri G, Normandin M, Guehl N. Quantitative Measurement of Tau Burden in a Dual-Time-Window Dynamic PET Imaging Protocol with [18F]MK6240. Journal Of Nuclear Medicine 2025, 66: 1299-1306. PMID: 40533354, PMCID: PMC12320581, DOI: 10.2967/jnumed.125.270165.Peer-Reviewed Original ResearchPET Mapping of Receptor Occupancy Using Joint Direct Parametric Reconstruction
Marin T, Belov V, Chemli Y, Ouyang J, Najmaoui Y, Fakhri G, Duvvuri S, Iredale P, Guehl N, Normandin M, Petibon Y. PET Mapping of Receptor Occupancy Using Joint Direct Parametric Reconstruction. IEEE Transactions On Biomedical Engineering 2025, 72: 1057-1066. PMID: 39446540, PMCID: PMC11875991, DOI: 10.1109/tbme.2024.3486191.Peer-Reviewed Original ResearchCentral nervous systemReceptor occupancyLow-binding regionsPET scansSimulation resultsPreclinical in vivo experimentsDynamic PET scansPairs of baselineEstimation of receptor occupancyEstimation frameworkPET neuroimagingReconstruction frameworkModulating drugsTime activity curvesParametric reconstructionDevelopment of drugs[18F]MK-6240 Radioligand Delivery Indices as Surrogates of Cerebral Perfusion: Bias and Correlation Against [15O]Water
Fu J, Juttukonda M, Garimella A, Salvatore A, Lois C, Ranasinghe A, Efthimiou N, Sari H, Aye W, Guehl N, El Fakhri G, Johnson K, Dickerson B, Izquierdo-Garcia D, Catana C, Price J. [18F]MK-6240 Radioligand Delivery Indices as Surrogates of Cerebral Perfusion: Bias and Correlation Against [15O]Water. Journal Of Nuclear Medicine 2025, 66: 410-417. PMID: 39947916, PMCID: PMC11876731, DOI: 10.2967/jnumed.124.268701.Peer-Reviewed Original Research
2024
Diffusion-based Bayesian posterior distribution prediction of kinetic parameters in dynamic PET
Djebra Y, Liu X, Marin T, Tiss A, Dhaynaut M, Guehl N, Johnson K, Fakhri G, Ma C, Ouyang J. Diffusion-based Bayesian posterior distribution prediction of kinetic parameters in dynamic PET. 2024, 00: 1-1. DOI: 10.1109/nss/mic/rtsd57108.2024.10657955.Peer-Reviewed Original ResearchConditional variational autoencoderEfficient deep learning-based approachMarkov chain Monte CarloDenoising diffusion probabilistic modelDeep learning-based approachDiffusion probabilistic modelLearning-based approachApproximate posterior distributionPosterior distributionVariational autoencoderHeavy computationTau protein aggregationBayesian inferenceProbabilistic modelData-DrivenStudy molecular processesBayesian posterior distributionProtein aggregationMetropolis-Hastings Markov chain Monte CarloMolecular processesAlzheimer's diseaseNeurodegenerative diseasesKinetic parametersEstimate posterior distributionsAutoencoderEffects 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 ResearchDiffusion Model-Based Posterior Distribution Prediction for Kinetic Parameter Estimation in Dynamic PET
Djebra Y, Liu X, Marin T, Tiss A, Dhaynaut M, Guehl N, Johnson K, Fakhri G, Ma C, Ouyang J. Diffusion Model-Based Posterior Distribution Prediction for Kinetic Parameter Estimation in Dynamic PET. 2011 IEEE International Symposium On Biomedical Imaging: From Nano To Macro 2024, 00: 1-5. PMID: 39530051, PMCID: PMC11554386, DOI: 10.1109/isbi56570.2024.10635805.Peer-Reviewed Original ResearchPosterior distributions of kinetic parametersDenoising diffusion probabilistic modelHyperphosphorylated tauP-tauDiffusion probabilistic modelAlzheimer's diseaseNeurodegenerative diseasesKinetic parametersPosterior distributionInference efficiencyComputational needsEstimate kinetic parametersProbabilistic modelComputation time