ABSTRACT
Objective ToinvestigatethevalueofenhancedT1WIhistogramanalysisintheidentificationofprimarycentralnervous systemlymphomas(PCNSL)andglioblastomas(GBM).Methods 41casesPCNSLand30casesofGBM confirmedbypathology wereanalyzedretrospectivelyinourhospital.TheT1WI,T2WI,andenhancedT1 MRimagesofthetwogroupswerecollected,andthe MaZdawasusedtoextracttheregionofinterestROIofthetumor.Thehistogramanalysiswasperformedonthemaximalregionof interestofthetumor.Thehistogramfeaturesofthetumors,includingthemean,variance,skewness,kurtosis,andthe1,10,50,90,and 99percentiles,wereusedtofindsignificantdifferencesbetweenthetwogroups.Results Amongthe9parametersextractedfromhistogram analysis,themean,variance,skewness,1st,10th,and50thpercentileswerestatisticallysignificant (P＜0.05).Therewasnosignificant differenceinkurtosis,90thpercentile,and99thpercentile(P＞0.05).Amongtheseparameters,skewnesswasthemosteffectivein identifyingPCNSLandGBM.TheareaundertheROCcurvewas0.960,whilethesensitivityandspecificitywere80%and100%, respectively.Conclusion Thehistogramanalysiscanprovidemoreinformationaboutquantitativeparameters.Amongthem,theskewness hashighdiagnosticefficiency,andprovidesnewideasandmethodsfordifferentialdiagnosisofPCNSLandGBMinthecentralnervous system.
ABSTRACT
Objective To investigate the difference of the motif patterns in brain directed functional network between first-episode schizophrenia patients and healthy controls, and to analysis the alterations of the underlying information flow patterns in patient networks. Methods The resting-state functional MRI data were collected from 44 first-episode schizophrenia patients and 39 healthy controls. The convergent cross mapping approach was employed to measure the causality connections between brain regions, and the directed functional networks were constructed. The calculations of the frequency and probability spectrum of all motif classes were performed at both whole brain and modular connected level. The between-group difference was then calculated. Results Compared with healthy controls, the frequency spectrum values of all motif classes in schizophrenia were significantly reduced (P＜0.05, FDR corrected), the Z scores of frequency spectrum of were decreased in chain-like motifs and increased in loop-like motifs. In the two groups, the probability values were higher at modular level than at whole brain level in two loop-like motifs (P＜0.05). Conclusion The present study revealed a loss in brain directed functional connections and abnormal alterations in the basic information flow patterns in first-episode schizophrenia brain.