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 ResearchConceptsLow 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 images
2016
Dual-Energy CT Reconstruction Using Guided Image Filtering
Yang H, Kim K, Fakhri G, Kang K, Xing Y, Li Q. Dual-Energy CT Reconstruction Using Guided Image Filtering. 2016, 1-4. DOI: 10.1109/nssmic.2016.8069594.Peer-Reviewed Original ResearchGuided image filterDual-energy CT reconstructionImage filteringX-ray spectraEdge-preserving smoothingImage filtering algorithmReduce beam hardening artifactsCT reconstruction methodCT reconstructionReconstruction methodBeam hardening artifactsImage reconstruction methodImage processing algorithmsLow energyOrdered subsets algorithmDual-energy CTGuided image filtering algorithmConvergence speedProcessing algorithmsDual-energy computed tomographyAttenuation measurementsEarly iterationsFiltering algorithmDual-energyAlgorithm
2014
Sparse-View Spectral CT Reconstruction Using Spectral Patch-Based Low-Rank Penalty
Kim K, Ye J, Worstell W, Ouyang J, Rakvongthai Y, Fakhri G, Li Q. Sparse-View Spectral CT Reconstruction Using Spectral Patch-Based Low-Rank Penalty. IEEE Transactions On Medical Imaging 2014, 34: 748-760. PMID: 25532170, DOI: 10.1109/tmi.2014.2380993.Peer-Reviewed Original ResearchConceptsLow-rank penaltySelf-similarity of patchesLog-likelihoodPoisson log-likelihoodCost functionSpectral CT reconstructionOriginal cost functionGPU implementationAlternating minimizationSensitive to intensity changesConventional algorithmsSpectral imagingEdge directionComputational costProcedure algorithmComputational advantagesAlgorithmX-ray transmissionComputer simulationsOptimization methodSpectral computed tomographySelf-similarityCT reconstructionX-rayGPU