3.0T MR正常肾脏短期重复DWI扫描:ADC值及IVIM参数值的可重复性分析  

Short-term reproducibility of apparent diffusion coefficient and intravoxel incoherent motion parameters in normal kidney at 3T scanner

作　　者：江舒 江建芹 孙昊 周笑 朱明明 周仪 符益纲 JIANG Su;JIANG Jian-qin;SUN Hao;ZHOU Xiao;ZHU Mingming;ZHOU Yi;FU Yigang(Department of MRI,Yancheng City No.1 People's Hospital,Jiangsu 224001,China)

机构地区：[1]盐城市第一人民医院磁共振室,江苏224001 [2]中国医学科学院北京协和医院放射科,北京100000

出　　处：《放射学实践》2018年第8期806-810,共5页Radiologic Practice

摘　　要：目的:探讨正常肾脏的ADC值及体素内不相干运动(IVIM)参数值在短期重复扫描时的可重复性。方法:对17例年轻志愿者短期内(间隔15分钟)进行2次双肾3.0T磁共振IVIM-DWI扫描。由2位测量者分别在ADC和IVIM图像上选取肾门层面测量肾皮质的ADC值和D、D*和f值。采用配对t检验(正态分布数据)或Wilcoxon检验(非正态分布数据)比较不同测量者和两次扫描获得的各参数的差异。对各参数值的测量者间一致性及两次扫描数据的可重复性采用组内相关系数(ICC)和Bland-Altman法进行评价。结果:重复扫描和两位医师重复测量获得的ADC和IVIM相关参数值的差异均无统计学意义(P>0.05)。双侧肾脏各参数测量值的差异均无统计学意义(P>0.05)。所有参数均表现出较好的测量者间一致性(ICC=0.703~0.973)。两次扫描时以ADC和D值的可重复性较好(ICC分别为0.756~0.866和0.779~0.876),D*和f值的可重复性较差(ICC分别为0.274~0.700和0.499~0.664)。结论:肾脏IVIM-DWI短期重复扫描时,以ADC和D值的可重复性较好。仍需要优化IVIM扫描方案和改进后处理算法,提高D*和f值的测量可重复性。Objective:To investigate the reproducibility of magnetic resonance apparent diffusion coefficient and intravoxel Incoherent motion(DW-IVIM)in normal kidney.Methods:Seventeen young healthy volunteers underwent free-breathing DWI-IVIM examination twice at a 3.0 Tesla MR scanner.Regions of interest were drawn on apparent diffusion coefficient(ADC)maps and IVIM maps to measure values of ADC and IVIM parameters(D,D*and f)by two independent observers.All the parameters were compared between repeated measurements,different observers and repeated scans using the paired-sample t-test(normal distribution)or Wilcoxon signed-rank test(non-normal distribution).Inter-observer agreement and inter-scanning reproducibility were assessed using interclass correlation coefficient(ICC)with Bland-Altman analysis.Results:There was no significant difference between the twice measurements and the twice scans in both ADC and IVIM parameters(P>0.05).There was no statistically significant difference in the parameters between bilateral kidneys.ADC and D showed good inter-observer agreement(ICC=0.703~0.973).The reproducibility of ADC and D between the twice scanning was good(ICCs for ADC were 0.756~0.866,ICCs for D were 0.779~0.876).Conclusion:In kidney IVIM-DWI,ADC and D showed good inter-observer agreement and short term reproducibility.Improvement of IVIM scanning technology and post-processing algorithms are needed to improve the measurement reproducibility of D*and f.

关 键 词：肾脏 磁共振成像 表观扩散系数 体素内不相干运动 可重复性 

分 类 号：R445.2[医药卫生—影像医学与核医学] R334.1[医药卫生—诊断学]