正常肝脏扩散峰度成像的可行性及可重复性研究  

Diffusion Kurtosis Imaging of Normal Liver:Study of Its Feasibility and Reproducibility

作　　者：谢丽芬[1] 陈世林 刘再毅[1] 梁长虹[1] 

机构地区：[1]广东省人民医院( 广东省医学科学院) 放射科,广州510080 [2]湖南省永州市中心医院放射科,425006

出　　处：《临床放射学杂志》2015年第5期797-802,共6页Journal of Clinical Radiology

基　　金：国家自然科学基金项目(编号:81271654);国家自然科学基金项目(编号:81271569);广州市科技支撑项目(编号:2010J-E481)

摘　　要：目的研究正常肝脏扩散峰度成像（DKI）的可行性及参数测量的可重复性。方法使用飞利浦1.5 T MR扫描仪和相同的序列及参数,对35名年轻志愿者进行2次肝脏DKI扫描,生成平均扩散系数（MD）图和平均峰度系数（MK）图。在左、右肝内分别选取上、中、下3个代表性层面的左、中、右9个测量位置,每个位置放置大小相同的感兴趣区（ROI）,分别测量并比较各ROI的MD值和MK值及左、右肝各9个ROI的平均参数值,并评估各参数测量的可重复性。结果前后2次DKI扫描b=800 s/mm2图像上肝脏的信噪比（SNR）较好,差异无统计学意义（P〉0.05）。2次扫描左、右肝内不同测量部位的MD、MK值差异均无统计学意义（P〉0.05）,其中右肝中层及左肝下层的MD、MK值可重复性较好。左肝的平均MD值、MK值较右肝高（t=-5.665～8.095,P〈0.001）,但左肝的平均MD、MK值可重复性均较右肝差;MD值、MK值的可重复性相近。结论初步研究结果表明,正常肝脏DKI是可行的,右肝中层和左肝下层的MD、MK值的可重复性较好;左肝的平均MD、MK值较右肝高,但可重复性较右肝差,MD、MK值的可重复性相似。Objective To investigate the clinical feasibility and parameter measurement reproducibility of diffusion kur- tosis imaging （DKI） for normal liver. Methods Thirty-five healthy young volunteers underwent liver DKI examination twice using the same sequences and parameters setting with a 1.5-T Philips MR scanner. MD （ mean diffusion coefficient） and MK （mean diffusion kurtosis） maps were generated and measured. Three representative sections, including superior, central and inferior sections, were separately selected on the left and right liver lobes. Then each selected section was divided into left, middle and right parts, finally nine measuring positions were obtained on each lobe. Regions of interest （ROIs） of the same size were placed on each position, then MD and MK values of each ROI were measured and their average values for each liver lobe were calculated and compared. The reproducibility of MD and MK measurements was also e- valuated. Results Signal-to-noise ratios （SNR） of the two sets of DKI images at b = 800 s/mm2 were good, showing no significant difference （ P 〉 0.05 ）. MD and MK values of different positions in each lobe during two examinations showed no significant difference （ P 〉 0.05 ）. The central section of the right lobe and the inferior section of the left lobe had the best reproducible MD and MK values. The average MD and MK values of the left liver lobe were significantly higher than those of the right lobe （ t = - 5. 665 - 8. 095, P 〈 0. 001 ）, but the averages of the left lobe showed poor reproducibility to the right lobe. In addition, the reproducibility of the average MD and MK values of both lobes were similar. Conclusion This preliminary study indicates that DKI is feasible for the study of normal liver. The right central section and the left infe- rior section show the best reproducible MD and MK values. The average MD and MK values of the left lobe are higher that those of the right lobe, although the reproducibility is poorer. The reproducibility

关 键 词：肝脏 扩散加权成像 扩散峰度成像 可行性 可重复性 

分 类 号：R445.2[医药卫生—影像医学与核医学]