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 equationArterial spin labeled perfusion imaging with balanced steady-state free precession readout and radial sampling
Han P, Marin T, Zhuo Y, Ouyang J, El Fakhri G, Ma C. Arterial spin labeled perfusion imaging with balanced steady-state free precession readout and radial sampling. Magnetic Resonance Imaging 2023, 102: 126-132. PMID: 37187264, PMCID: PMC10524790, DOI: 10.1016/j.mri.2023.05.005.Peer-Reviewed Original ResearchConceptsOff-resonance effectsBalanced steady-state free precessionPhase-cycling techniqueTemporal SNRBalanced steady-state free precession acquisitionRadial sampling schemeSpoiled gradient-recalled acquisitionRadial samplingCartesian sampling schemeBalanced steady-state free precession readoutK-space dataSampling schemeSpin labelingSteady-state free precessionK-spaceImage readoutBanding artifactsMotion-related artifactsReadoutFree precessionArterial spin labelingImage reconstructionParallel imagingImaging timePerfusion-weighted imaging
2022
Joint spectral quantification of MR spectroscopic imaging using linear tangent space alignment‐based manifold learning
Ma C, Han P, Zhuo Y, Djebra Y, Marin T, Fakhri G. Joint spectral quantification of MR spectroscopic imaging using linear tangent space alignment‐based manifold learning. Magnetic Resonance In Medicine 2022, 89: 1297-1313. PMID: 36404676, PMCID: PMC9892363, DOI: 10.1002/mrm.29526.Peer-Reviewed Original ResearchConceptsSubspace-based methodsManifold learningIntrinsic low-dimensional structureGlobal coordinationLearning-based methodsNumerical simulation dataSpatial smoothness constraintSparsity constraintSpace alignmentSubspace modelSmoothness constraintSuperior performanceRoot mean square errorLinear transformationMechanical simulationsLow-dimensionalSquare errorSubspaceExperimental dataSpectroscopic imagingQuantum mechanical simulationsCoordinate alignmentMR spectroscopic imagingSpectral quantificationSimulated data
2021
In vivo imaging of mGlu5 receptor expression in humans with Fragile X Syndrome towards development of a potential biomarker
Mody M, Petibon Y, Han P, Kuruppu D, Ma C, Yokell D, Neelamegam R, Normandin M, Fakhri G, Brownell A. In vivo imaging of mGlu5 receptor expression in humans with Fragile X Syndrome towards development of a potential biomarker. Scientific Reports 2021, 11: 15897. PMID: 34354107, PMCID: PMC8342610, DOI: 10.1038/s41598-021-94967-y.Peer-Reviewed Original ResearchConceptsFragile X syndromeFragile X mental retardation proteinX syndromeLoss of fragile X mental retardation proteinMGlu5 receptor expressionMetabotropic glutamate subtype 5 receptorsDrug occupancy studiesSignificant group differencesFragile X mental retardationHealthy controlsAnterior cingulateMGluR5 availabilityVisuospatial processingMGlu5 receptorsOlfactory cortexBrain areasGroup differencesRetardation proteinGlutamate signalingImages of maleNeurodevelopmental disordersExcessive glutamate signalingGender-matched controlsDisordersMGluR5
2019
Arterial spin labeling MR image denoising and reconstruction using unsupervised deep learning
Gong K, Han P, Fakhri G, Ma C, Li Q. Arterial spin labeling MR image denoising and reconstruction using unsupervised deep learning. NMR In Biomedicine 2019, 35: e4224. PMID: 31865615, PMCID: PMC7306418, DOI: 10.1002/nbm.4224.Peer-Reviewed Original ResearchConceptsSignal-to-noise ratioImage denoisingReconstruction frameworkDeep learning-based image denoisingDeep learning-based denoisersMR image denoisingLearning-based denoisingLow signal-to-noise ratioK-space dataNoisy imagesTraining labelsTraining pairsNetwork inputNeural networkDenoisingIn vivo experiment dataSuperior performanceImaging speedReconstruction processImage qualityLong imaging timesNetworkFrameworkImagesSpatial resolution
2016
DC artifact correction for arbitrary phase-cycling sequence
Han P, Park H, Park S. DC artifact correction for arbitrary phase-cycling sequence. Magnetic Resonance Imaging 2016, 38: 21-26. PMID: 27998747, DOI: 10.1016/j.mri.2016.12.015.Peer-Reviewed Original ResearchInvestigation of control scans in pseudo‐continuous arterial spin labeling (pCASL): Strategies for improving sensitivity and reliability of pCASL
Han P, Choi S, Park S. Investigation of control scans in pseudo‐continuous arterial spin labeling (pCASL): Strategies for improving sensitivity and reliability of pCASL. Magnetic Resonance In Medicine 2016, 78: 917-929. PMID: 27690322, DOI: 10.1002/mrm.26474.Peer-Reviewed Original Research
2015
Whole‐brain perfusion imaging with balanced steady‐state free precession arterial spin labeling
Han P, Ye J, Kim E, Choi S, Park S. Whole‐brain perfusion imaging with balanced steady‐state free precession arterial spin labeling. NMR In Biomedicine 2015, 29: 264-274. PMID: 26676386, DOI: 10.1002/nbm.3463.Peer-Reviewed Original ResearchConceptsSignal-to-noise ratioBalanced steady-state free precessionTotal scan timeCompressive sensingReduced susceptibility artifactsPerfusion imagingWhole-brain perfusion imagingScan timeSusceptibility artifactsPseudo-continuous ASLReadout timeCS approachSteady-state free precessionAcquisition of perfusion imagesSegmentation approachFree precessionBSSFP readoutArterial spin labeling (ASL) perfusionSpatial resolutionImage qualityDistortion-freeReadoutHigh-resolutionTemporal resolutionImagesInter-Slice Blood Flow and Magnetization Transfer Effects as A New Simultaneous Imaging Strategy
Han P, Barker J, Kim K, Choi S, Bae K, Park S. Inter-Slice Blood Flow and Magnetization Transfer Effects as A New Simultaneous Imaging Strategy. PLOS ONE 2015, 10: e0140560. PMID: 26466316, PMCID: PMC4605487, DOI: 10.1371/journal.pone.0140560.Peer-Reviewed Original ResearchConceptsAlternate ascending/descending directional navigationPseudo-continuous ASLBlood flowPulsed ASL methodClinically reasonable timeMT asymmetryBlood flow signalsMaps of blood flowSimultaneous blood flowCerebral blood flow signalsPreparation RF pulseFlip anglePerfusion signalBSSFP readoutMT ratioFlow signalsImaging strategiesMagnetization transferASL methodLabeling planeRF pulsesMagnetization transfer effectsSuperposition of signalsCompressed Sensing for fMRI: Feasibility Study on the Acceleration of Non‐EPI fMRI at 9.4T
Han P, Park S, Kim S, Ye J. Compressed Sensing for fMRI: Feasibility Study on the Acceleration of Non‐EPI fMRI at 9.4T. BioMed Research International 2015, 2015: 131926. PMID: 26413503, PMCID: PMC4564593, DOI: 10.1155/2015/131926.Peer-Reviewed Original ResearchConceptsCompressive sensingBalanced steady-state free precessionSensitive to image distortionsHigh-resolution fMRI techniqueMagnetic field inhomogeneityLocal magnetic field inhomogeneitiesConventional functional magnetic resonance imagingCS reconstructionGradient-recalled echoCS algorithmFOCUSS algorithmNon-EPI sequencesMagnetic fieldSampling patternHigh-resolution functional magnetic resonance imagingFunctional magnetic resonance imagingField inhomogeneityGRE-EPIImage distortionSteady-state free precessionExperimental resultsTemporal resolutionAlgorithmFree precessionSpoiled gradient echoInvestigation of Inter-Slice Magnetization Transfer Effects as a New Method for MTR Imaging of the Human Brain
Barker J, Han P, Choi S, Bae K, Park S. Investigation of Inter-Slice Magnetization Transfer Effects as a New Method for MTR Imaging of the Human Brain. PLOS ONE 2015, 10: e0117101. PMID: 25664938, PMCID: PMC4321840, DOI: 10.1371/journal.pone.0117101.Peer-Reviewed Original ResearchConceptsBalanced steady-state free precessionFlip angleMagnetization transferMagnetization transfer effectsSteady-state free precessionSaturation pulseModel of MTFree precessionMT-weightedAcquisition parametersMT effectMT ratioDelay timePrecessionMTR imagesHigh SNRInterslicePE stepsMagnetizationFlip