3d gre t2衰减校正水脂分离技术在脂肪肝定量检测中的初步研究.docx

3dgret2衰减校正水脂分别技术在脂肪肝定量检测中的初步探讨为15.38%o经Wilcoxon符号秩检验，两者间差异有统计学意义(Plt;0.01)oHFFMRS和HFF3DRGREMRI呈线性正相关；回来直线方程为：HFF3DGREMRI=1.3199HFFMRS+2.8553,R2=0.9489；Spearson秩相关系数为0.963(Plt;0.01)oHFF3DGREMRI高于HFFMRS。取HFFMRS大于5.56%为诊断脂肪肝的标准，利用ROC曲线分析HFF3DGREMRI值对肝脏脂肪含量评估的效能，计算曲线下面积AzHFF3DGREMRI=0.997(PltQOl)。HFF3DGREMRI界值取IL81%时，诊断灵敏度为1.0,特异性为0.952,阳性预料值为89.50%,阴性预料值为100%。结论：初步探讨结果显示3DGRET2*衰减校正水脂分别技术精确性较高，有潜力进行脂肪肝定量分析。关键词：脂肪肝；磁共振成像；水脂分别技术；定量分析2AbstractObjective:Toassesstheaccuracyofanewwater-fatseparationMRtechniquewhichiscalledvolumetricinterpolatedbreath-holdgradient-recalled-echoT2*effectcorrectedwater-fatseparationtechnique(3DGREMRI)infatquantificationinlivebyusing1H-MRspectroscopy(1H-MRS)asthereferencestandard.Materialsandmethods:FortysubjectsweretakenconventionalMRIexaminationofliverwhichincludingT1WI,T2WI,thein-phaseandopposed-phaseimaging.TworadiologistwithMRexperienceanalysedallimagesandjudgedwhetherthesubjecthadhepaticsteatosis.Thentheywereunderwentsinglevoxel1H-MRSand3DGREMRIoftheliver.TheMRIimagesandMRSspectrafeatureswereobservedandanalyzed.MRSwerecollectedatechotimeswith30,60,90,120,and150millisecondrespectively.TheT2*effectswerecorrectedbyusingalog-linearleastsquarefittingalgorithm.Accordingtothecorrectedareaunderthewaterpeak(Swater)andfatpeakarea(Sfat),theHFFMRS(hepaticfatfraction,HFF)wascalculated.ThevalueofHFFMRSwasusedasthestandardtoevaluatetheaccuracyof3DGREMRIindiagnosinghepaticsteatosis.3DGREMRIbasedontwopointsDIXONmethodandusedthesmallflipangletoinhibitT1effects.InordertocorrectT*effect,oneserialin-phaseandtwoserialopposed-phaseimageswerecollected.TheHFF3DGREM.