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Objective: To explore the microstructural damage of extrapyramidal system gray matter nuclei in Parkinson disease (PD) using diffusion kurtosis imaging (DKI). Materials and Methods: We enrolled 35 clinically confirmed PD patients and 23 healthy volunteers. All patients underwent MR examination with conventional MRI scan sequences and an additional DKI sequence. We subsequently reconstructed the DKI raw images and analyzed the data. A radiologist in our hospital collected the Mini-Mental State Examination (MMSE) score of all subjects. Results: In the PD group, the mean kurtosis and axial kurtosis level decreased in the red nucleus (RN) and thalamus; the radial kurtosis increased in the substantia nigra (SN) and globus pallidus (GP). Fractional anisotropy decreased in the putamen. The largest area under the ROC curve of mean diffusion in GP was 0.811. Most kurtosis parameters demonstrated a positive correlation with the MMSE score, while several diffusion parameters showed a negative correlation with the same. Conclusion: DKI can qualitatively distinguish PD from healthy controls; furthermore, DKI-derived parameters can quantitatively evaluate the modifications of microstructures in extrapyramidal system gray matter nucleus in PD.
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Objective ToinvestigatethefeasibilityofassessingliverfunctiongradingbyIDEAL-IQsequenceon1.5T MR.Methods The patientswhowereclinicallydiagnosedaslivecirrhosisandunderwent1.5T MRIDEAL-IQsequenceinourhospitalfrom February 2016toDecember2017wereanalyzedretrospectively.TheyweredividedintoA,BandCgradesaccordingtotheChild-Pughgrading standardofliverfunction.Finally,therewere30patientsinChild-PughA,25patientsinChild-PughBand16patientsinChild-Pugh C.ThefatratiomapsandR2?relaxationratemapswereusedtomeasuretheliverfatcontentandironcontentbythetwoobservers onAW4.6workstation,respectively.ThemeanvaluesofthefatfractionsandtheR2?valuesweremeasuredandcomparedbyusing K ruskal-W allis H testamongthethreegroups.Then,thegroupAandBwerecombinedtoestablishthepredictivemodelindiagnosingthegroup Cbyusingthe L o g istic regressionanalysis,whichcombinedthefatfractionandR2?value.TheROCcurvewasdrawntoobtainedtheAUC,and calculatedthesensitivityandthespecificitywiththeoptimalthreshold.Results Thereweregoodconsistencyofmeasurementdata betweenthetwoobserves(ICC>0.8).ThefatfractionandR2?valueincreasedwiththedecreaseoftheliverfunction.Thefatfractionsofthe Child-PughA,BandCgroupwere(3.58±0.91)%,(3.64±1.20)%,(6.87±3.91)%,respectively.TheR2?valuesoftheChild-Pugh A,BandCgroupswere(33.31±11.80)Hz,(38.00±13.31)Hz,(58.98±44.54)Hz,respectively.TheAUCofwhichcombinedfat fractionandR2?valuediagnosingChild-PughCwas0.843.Thesensitivityandthespecificitywere81.8% and81.3%,respectively. Conclusion The1.5T MRIDEAL-IQsequencecanbeusedtoevaluatetheliverreserveunctionoflivercirrhosispatientsaccording ffatfractionandR2?value,especiallyfortheChild-PughCcirrhosis patientswithhighsensitivityandspecificity.
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Objective To explore the value of diffusion tensor imaging (DTI) in differential diagnosis of intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC).Methods Fifty-two patients including 20 patients with ICC (ICC group) and 32 patients with HCC (HCC group) confirmed by histopathological examination were recruited in the study.All the patients were performed MR exams on a 1.5T scanner in a protocol containing the routine T1WI,T2WI,DWI and DTI.The values of ADC,fractional anisotropy (FA),diffusion coefficient (D) were blindly reviewed and analyzed by two experienced observers,and were compared between two groups.The ROC curve was used to evaluate the di agnostic efficiency.Results The border clear percentage of ICC group (9/20,45.00％) had no significant difference compared with that of HCC group (15/32,46.88％;x2 =0.02,P=0.90),the detection rate of bile duct expansion in ICC group (11/20,55.00％) was higher than that in HCC group (4/32,12.50％;x2=10.83,P=0.001).Theintraclasscor relation coefficient value of ADC,D and FA in the ICC group and HCC group were all more than 0.90.The mean FA of ICCgroup (0.45±0.16) were significantly higher than that of HCC group (0.30±0.13;P=0.001),while the mean ADC and D values in ICC and HCC groups had no significant difference (both P＞0.05).The area under the ROC curve of FA was 0.76.And when FA=0.31,there was a higher sensitivity (85.0％) in identifying ICC and HCC.Conclusion The FA of DTI shows a stronger capability than the ADC and D values in differentiating the ICC from HCC.
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Objective To evaluate the diagnostic performance of the histogram analysis of mono-exponential and intravoxel incoherent motion(IVIM) models to the dualistic model of epithelial ovarian cancer(EOC). Methods Forty female patients with histopathologically proven epithelial ovarian cancer underwent preoperative MR examination. Scanning sequences included conventional imaging, diffusion-weighted magnetic resonance imaging with 11 b values (0, 30, 50, 100, 150, 200, 400, 600, 800, 1 000, 1 500 s/mm2) and dynamic contrast enhanced MRI (DCE-MRI). Based on the dualistic model of EOC, all patients were divided into two groups:typeⅠ(low grade, n=16) and typeⅡ(high grade, n=24). ADC, D, D*and f maps and their corresponding histograms were generated by post-processing software. Based on an entire-tumour measurement, the following histogram parameters were recorded, respectively: (a) Mean; (b) the 10th percentile (10th);(c) the mean of the top 10 percent (MeanL);(d) the 90th percentile (90th);(e) the mean of the bottom 10 percent (MeanR). Two types were compared using independent sample t test or Mann-Whitney U test. And areas under ROC curve between two groups were assessed. Results For ADC , D, and f, all indices(Mean,10th,MeanL,90th,MeanR) of the histogram were significantly lower in typeⅡthan in type Ⅰ(P0.05). D demonstrated a comparable accuracy with ADC in differentiating the grade of EOC (area under curve: Mean, 0.898 vs. 0.893; 10th, 0.880 vs. 0.846; MeanL, 0.878 vs. 0.858; 90th, 0.895 vs. 0.839; MeanR, 0.872 vs. 0.814), and both ADC and D have better performance than f. Conclusion It is feasible to stratify the grade of EOC by mono-exponential and IVIM models with histogram metrics,diagnositic efficiency of ADC and D values are higher.