移植肾小视野高分辨多b值DWI研究  

High resolution diffusion weighted imaging of renal allograft with multiple b-values

作　　者：李延军[1,2] 谢媛 张龙江[1,2] 卢光明 

机构地区：[1]南京军区南京总医院 [2]南京大学医学院附属金陵医院医学影像科,南京210002

出　　处：《放射学实践》2015年第5期504-508,共5页Radiologic Practice

基　　金：中国博士后科学基金面上项目(2014M552702)

摘　　要：目的:探讨小视野高分辨多b值磁共振扩散加权成像(rFOV DWI)在移植肾功能评估中的应用价值。方法:选取肾移植患者41例行rFOV DWI检查。依据估算的肾小球滤过率将患者分为3组(1组:8例,eGFR<30mL/min·1.73m2;2组:19例,30mL/min·1.73m2≤eGFR<60mL/min·1.73m2;3组:14例,eGFR≥60mL/min·1.73m2)。分别测量皮髓质的表观扩散系数(ADC)值、单纯扩散系数D值和灌注分数f值,采用单因素方差分析比较组间差异,采用Pearson相关系数判断各参数与eGFR的相关性,采用ROC曲线判断各参数诊断移植肾功能损伤的效能。结果:随着移植肾功能的减低,ADC值、f值均呈下降趋势,其中1组皮质ADC值显著低于2、3组(P<0.05);皮质f值3组间两两比较差异均有统计学意义(P<0.05);1组髓质f值显著低于3组(P<0.05);余各组间参数比较差异均无统计学意义(P>0.05)。皮质ADC值、皮髓质f值均与eGFR呈显著正相关(r值分别为0.398、0.673、0.413,P<0.05)。以0.283为截点,皮质f值诊断移植肾功能轻中度以上受损的敏感度、特异度分别为93%和59%。结论:小视野多b值扩散加权成像可无创性评估移植肾功能。Objective：To investigate the feasibility of high resolution diffusion weighted imaging （DWI） with muhi-b values using reduced field of view （rFOV） as a noninvasive way for assessing the function of renal allografts. Methods：For- ty-one kidney transplant recipients underwent MR examination. According to the estimated glomerular filtration rate （eG- FR） ,subjects were divided into three groups：group 1 （n=8） with eGFR （3030 mL/min ·1.73m2 ;group 2 （n= 19） with 30mL/min·1.73m2≤eGFR（60 mL/min· 1.73m2 ;group 3 （n= 14） eGFR≥60 mL/min·1.73m2. Apparent diffusion coef- ficient （ADC）,pure diffusion （D） and perfusion fraction （f） were calculated separately for the cortex and the medulla and compared among the three groups using one way ANOVA. Correlations between imaging results and renal allograft function determined by eGFR were also assessed. ROC curves were used for assessing the diagnostic performance of impaired renal function. Results：There was a gradually decreasing trend of ADC and I in both cortex and medulla from group 3 to group 1 following the decreasing of renal allograft function. Mean value of cortical ADC was significantly lower in group 1 than those of group 2 and group 3,respectively. Cortical f showed significant differences between each of two groups and medullary f in group 1 was significantly lower than that of group 3. Cortical ADC,f and medullary f correlated positively and significantly with eGFR （r=0. 398,0. 673,0. 413 ,respectively,P〈0.05）. The sensitivity and specificity of rFOV DWI for diagnosing the function of renal allograft with impaired renal allograft function more than mild-moderate degree were 93 and 59% ,respectively,when cortical f〈0. 283 was used as the cutoff value. Conclusion： rFOV DW1 with multi-b values in transplanted kidneys is a promising tool for non-invasive functional monitoring.

关 键 词：扩散加权成像 磁共振成像 肾移植 灌注 

分 类 号：R699.2[医药卫生—泌尿科学] R445.2[医药卫生—外科学]