应用扩散加权成像双指数模型评价慢性肾脏病的初步研究  

Preliminary Study of Biexponential Model of Diffusion Weighted Imaging in Evaluation of Chronic Kidney Disease

作　　者：李琼[1] 张泉[2] 孙浩然[2] 林珊 白人驹[2] 

机构地区：[1]天津市南开医院放射科,300100 [2]天津医科大学总医院放射科,天津300052 [3]肾科

出　　处：《临床放射学杂志》2012年第7期970-974,共5页Journal of Clinical Radiology

基　　金：天津市自然科学基金资助项目(编号:08JCYBJC07900)

摘　　要：目的应用扩散加权成像(DWI)双指数模型计算肾脏皮髓质的纯扩散系数(ADCd)及灌注分数(Fp),并分析其在慢性肾脏病(CKD)患者评价中的应用价值。方法搜集临床确诊的52例CKD患者和27名健康志愿者,分别行0、50,0、100,0、500,0、1000(s/mm2)四组b值的DWI检查,根据体素内不相干运动(IVIM)的双指数模型计算肾脏皮髓质的ADCd和Fp值,分析CKD患者皮髓质ADCd、Fp值的变化规律及其与肾小球滤过率估算值(eG-FR)之间的相关性。结果正常对照组肾脏皮质ADCd值显著大于髓质(P<0.05)。正常对照组、CKD轻度损害组和中重度损害组之间的肾脏皮髓质ADCd值均存在显著性差异(正常对照组>CKD轻度损害组>CKD中重度损害组)(P<0.001),三组之间的肾脏皮髓质Fp值均存在显著性差异(正常对照组>CKD轻度损害组>CKD中重度损害组)(P<0.001)。CKD患者的皮髓质ADCd值、髓质Fp值与eGFR均呈正相关(P<0.05)。结论 DWI双指数模型能够得到反映肾脏真实水分子扩散运动及微循环灌注的指标,肾脏皮髓质ADCd值及髓质Fp值可以在一定程度上反映CKD患者的肾脏功能改变。Objective To determine the role of true diffusion coefficient （ADCd） and perfusion fraction （Fp） of cortex and medulla with biexponential model of diffusion weighted imaging （ DWI ） in evaluation of chronic kidney disease （CKD）. Methods 52 patients with CKD and 27 healthy volunteers were included. All of them received DWI examina- tions with four groups of b value, including 0,50, 0,I00, 0,500 and 0,1000 （s/ram2）. The ADCd and Fp of cortex and medulla were calculated according to the biexponential model of intravoxel incoherent motion （ IVIM ）. Correlations of corti- cal and medullary ADCd and Fp with estimated glomerular filtration rate （eGFR） were analyzed in CKD patients. Results The cortical ADCd was significantly higher than that of medulla in control group （ P 〈 0.05 ）. There were statistical differences among the control group, minor CKD group and moderate/severe CKD group in the cortical and medullary ADCd values （ control group 〉 minor CKD group 〉 moderate/severe CKD group） （ P 〈 0.001 ）. Significant differences in cortical and medullary Fp also were obtained among three groups （control group 〉 minor CKD group 〉 moderate/severe CKD group） （P 〈 0.001 ）. Positive correlations with eGFR were found in the cortical and medullary ADCd and medullary Fp of CKD patients （ P 〈 0.05 ）.. Conclusion Biexponential model of DWI can reflect the true water diffusion motion and mi- crocirculation peffusion in kidney. The cortical and medullary ADCd and medullary Fp can reflect the renal functional changes in patients with CKD to some extent.

关 键 词：慢性肾脏病 扩散加权成像 体素内不相干运动 双指数模型 

分 类 号：R445.2[医药卫生—影像医学与核医学] R692[医药卫生—诊断学]