肾脏3.0 T磁共振弥散张量成像b值等参数优化及可重复性研究  

B value and other parameters optimization of renal DTI at 3.0 T MRI and repeatability of measurements

作　　者：王玉婷[1] 鄢雄[1] 尹芳艳 赖力[1] 印隆林[1] WANG Yu-ting;YAN Xiong;YIN Fang-yan;LAI Li;YIN Long-lin(Department of Radiology,Sichuan Academy of Medical Sciences&Sichuan Provincial People's Hospital,Chengdu 610072,China)

机构地区：[1]四川省医学科学院·四川省人民医院放射科

出　　处：《实用医院临床杂志》2020年第1期53-56,共4页Practical Journal of Clinical Medicine

基　　金：电子科技大学中央高校基础研究项目(编号:ZYGX2015J125)

摘　　要：目的探讨肾脏3.0 T磁共振弥散张量成像(DTI)的最优b值,评估DTI测值的可重复性。方法对无肾脏疾病的志愿者行双肾DTI,预实验中对20例分别采用0,200 s/mm2;0,400 s/mm2;0,600 s/mm2三组b值,测量肾皮髓质各向异性分数(FA)之差最大者,定为最优b值。此条件下完成41例DTI,由两名观察者分别勾画感兴趣区,测量FA,其中一名测量两次。用组内相关系数(ICC)评价观察者内及观察者间的一致性。结果b值=0,200 s/mm2时双肾FA皮髓差最大(P=0.003)。在此b值下观察,肾脏髓质FA值高于皮质(P<0.001)。肾髓质FA的观察者间ICC稍低,为0.690;肾总体、皮质FA值的观察者内和观察者间、髓质FA的观察者内ICC均>0.8。结论肾脏DTI使用低b值可获得更好的皮髓质对比。除测量肾髓质FA值的观察者间一致性稍差之外,其它FA测值均有很高的可重复性。Objective To determine the optimal b value of renal diffusion tensor imaging(DTI)at 3.0 T magnetic resonance imaging(MRI),and assess the repeatability of measurements.Methods Normal kidneys of 20 volunteers were examined with DTI at 3.0 T MRI.In a pre-experiment,b values at 0,200 s/mm2,0,400 s/mm2and 0,600 s/mm2 were compared.The b value,which had the largest cortical-medullar differentiation on images,was set as the optimal value and used for renal DTI of 41 subjects.The area of interest was delineated and FA values were measured by two observers.Of the two observers,one observer measured twice.Intra-class correlation coefficient(ICC)was employed to measure the consistency.Results The largest cortical-medullar differentiation was obtained using b values at 0,200 s/mm2(P=0.003).Under this b value,medullary FA values were significantly greater than those of the cortex(P<0.001).The ICC of two observers measuring medullar FA was relatively low(0.690)and all other ICCs were above 0.8.Conclusion DTI of kidneys using 3.0 T MRI system can gain better cortical-medullar differentiation using lower b values.Measurements generally have good repeatability except that the inter-observer consistency of medullar FA was relatively low.

关 键 词：肾脏 弥散张量成像 B值 可重复性 

分 类 号：R445.2[医药卫生—影像医学与核医学]