2017
Low‐dose CT reconstruction using spatially encoded nonlocal penalty
Kim K, Fakhri G, Li Q. Low‐dose CT reconstruction using spatially encoded nonlocal penalty. Medical Physics 2017, 44: e376-e390. PMID: 29027240, PMCID: PMC5927365, DOI: 10.1002/mp.12523.Peer-Reviewed Original ResearchMeSH KeywordsHumansImage Processing, Computer-AssistedQuality ControlRadiation DosageTomography, X-Ray ComputedConceptsLow Dose CT Grand ChallengeDose imagesDose dataFlying focal spotQuadratic surrogatesLow-dose CT reconstructionCT reconstruction methodImage qualityRadiation doseCT phantomFBP imagesRaw projectionsRebinning methodFocal spotLog-likelihoodReconstructed test imagesEfficient memory usageNesterov's momentum methodPoisson log-likelihoodGrand ChallengeComputed tomographyLow radiation doseCT reconstructionAccurate diagnostic featuresTest imagesIterative Low-Dose CT Reconstruction With Priors Trained by Artificial Neural Network
Wu D, Kim K, Fakhri G, Li Q. Iterative Low-Dose CT Reconstruction With Priors Trained by Artificial Neural Network. IEEE Transactions On Medical Imaging 2017, 36: 2479-2486. PMID: 28922116, PMCID: PMC5897914, DOI: 10.1109/tmi.2017.2753138.Peer-Reviewed Original ResearchConceptsArtificial neural networkIterative reconstruction algorithmNeural networkLow-dose CT reconstructionReconstruction algorithmUnsupervised feature learningReconstructed imagesFeatures of imagesImprove reconstruction qualityNormal-dose imagesDecreasing radiation riskDevelopment of artificial neural networksFeature learningComplex featuresAuto-encoderReconstruction qualityData fidelityMachine learningSuppress noiseSmoothness constraintPhoton fluxPreservation abilityGrand ChallengeNoise reductionPriors
2013
Cardiac motion compensation and resolution modeling in simultaneous PET-MR: a cardiac lesion detection study
Petibon Y, Ouyang J, Zhu X, Huang C, Reese T, Chun S, Li Q, Fakhri G. Cardiac motion compensation and resolution modeling in simultaneous PET-MR: a cardiac lesion detection study. Physics In Medicine And Biology 2013, 58: 2085-2102. PMID: 23470288, PMCID: PMC3657754, DOI: 10.1088/0031-9155/58/7/2085.Peer-Reviewed Original ResearchConceptsContrast recoveryDetector point spread functionPartial volume effectsK-spaceMotion compensationB-spline registrationLesion-detection studiesCardiac motion compensationPET-MR scannersSimultaneous PET-MRPET contrastIterative reconstruction frameworkPoint spread functionMotion correctionPET countsNon-rigid B-spline registrationCardiac phantomPSF modelPET-MRMotion deblurringReconstruction frameworkSystem matrixCardiac PETSpread functionDefect detection
2009
Improved MAGIC gel for higher sensitivity and elemental tissue equivalent 3D dosimetry
Zhu X, Reese T, Crowley E, Fakhri G. Improved MAGIC gel for higher sensitivity and elemental tissue equivalent 3D dosimetry. Medical Physics 2009, 37: 183-188. PMID: 20175480, PMCID: PMC2801736, DOI: 10.1118/1.3260844.Peer-Reviewed Original ResearchConceptsMAGIC gelTissue equivalentsGel dosimeterRange verificationNuclear reactionsDosimetry applicationsProton beam therapyPhantom materialTime-activity measurementsDosimetry purposesTransverse relaxation rateRelaxation rateBeam therapyDose-response curveSlopes of dose-response curvesGel formulationMAGICDose responseMelting pointSoft tissueDosimetersPhantomTime-activityProtonGlucose