目的:研究正常肝脏体素内不相干运动磁共振扩散加权成像的可行性及可重复性。方法使用飞利浦1.5T磁共振成像仪对35例年轻志愿者进行2次肝脏体素内不相干运动磁共振扩散加权成像扫描。利用飞利浦公司开发的软件生成体素内不相干运动相关的参数图(D、D*、f),选取左、右肝中间连续3层图像进行测量,每层图像放置6个(左、右肝分别各3个)大小一致的感兴趣区(ROI),分别计算左、右肝的各参数的平均值。分别比较左、右肝各种参数值及其可重复性(Bland-Altman方法)。结果左肝D、D*、f 值[D(×10-3 mm2/s):1.250±0.210,D*(×10-3 mm2/s):101.906±15.063,f(%):22.954±5.268]均较右肝[D(×10-3mm2/s):1.039±0.124,D*(×10-3mm2/s):100.127±20.757,f(%):18.317±3.671](D、f 值:P<0.001,D*值:P=0.232-0.605)高,同时左肝D、D*和 f值的可重复性(LOA 分别为22.55%,51.05%,39.3%)均较右肝低(LOA 分别为20.3%,39.25%,33.9%);其中左肝和右肝的D值的可重复性最好。结论肝脏体素内不相干运动磁共振扩散加权成像方法可行,左肝的D、D*和 f值较右肝高,但可重复性较右肝差;D值的可重复性最好。
Objective To investigate the feasibility of magnetic resonance diffusion-weighted intravoxel incoherent motion (DW-IVIM)imaging and its reproducibility in normal liver.Methods Thirty-five young healthy volunteers underwent liver DW-IVIM ex-amination twice on a 1 .5 Tesla Philips MR scanner.Parameter maps of D,D* and f were generated by using a manufacturer-sup-plied software.Six Region-of-interests (ROIs)(3 ROIs in left and right liver lobe,respectively)were drawn on three consecutive middle slices,respectively.The average values of D,D* and f were measured and compared between the left and right liver lobe. The reproducibility of D,D* and f measurement were assessed with Bland-Altman method.Results The values of D,D* and f of left liver lobe [D(×10-3 mm2/s):1.250±0.210,D*(×10-3 mm2/s):101.906±15.063 ,f(%):22.954±5.268]were statistically higher than those of right liver lobe[D(×10-3 mm2/s):1.039±0.124,D*(×10-3 mm2/s):100.127±20.757,f(%),18.317± 3.671](D,f,P<0.001,D*,P<0.232-0.605),however ,their reproducibility of left liver lobe [limit of agreement(LOA):22.55%,51.05%,39.3%,respectively]were lower than those of right liver lobe (LOA:20.3%,39.25%,33.9%).The D values had the best reproducibility in both the left and right liver lobe.Conclusion The liver DW-IVIM is feasible.The values of D,D*and f in left liver lobe were higher that those in right liver lobe but with worse reproducibility of measurement.The D value was most reproducible in both liver lobes.