目的：探讨肾脏血氧水平依赖（blood oxygen level-dependent,BOLD）磁共振成像（magnetic resonance imaging,MRI）评估慢性肾病（chronic kidney disease, CKD）早期肾缺氧的价值。方法：52例CKD患者（CKD组）和年龄、性别匹配的52名健康体检者（对照组）接受冠状面BOLD-MRI检查,分别测量肾脏皮、髓质R2*值。同时检测CKD患者的血清肌酐水平,运用Cockcroft-Gault公式计算获得估算肾小球滤过率,按照美国肾脏病基金会公布的肾脏病生存质量指导指南将CKD患者分为1~5期。比较对照组与CKD组、各CKD分期亚组间的肾脏皮质、髓质R2*值间的差异。结果：CKD组及对照组肾脏的髓质R2*值明显高于皮质R2*值（P<0.05）。CKD组[（16.40±2.47）/s]及CKD 1期组[（16.55±2.12）/s]、CKD 4期组[（16.48±2.95）/s]、CKD 5期组[（13.99±2.21）/s]的肾髓质R2*值均低于对照组[（18.17±2.38）/s]（P<0.05）。结论：肾脏BOLD-MRI检查可发现CKD 1期患者肾髓质R2*值的下降变化,提示BOLD成像对慢性肾病早期肾髓质缺氧变化敏感,可用于CKD早期肾功能损害的诊断。

Objective: To evaluate value of blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) for early renal hypoxia assessment in chronic kidney disease(CKD). Methods: Fifty-two patients with CKD and 52 age- and sex-matched health volunteers underwent BOLD MRI of the kidneys. Serum creatinine (sCr) levels and estimated GFR (eGFR) were collected. The patients were classified into 5 stages according to the National Kidney Foundation′s Kidney Disease Outcomes Quality Initiative. Difference in R2*s were compared between patients and volunteers and among different stages of CKD. Results: In patients with CKD and volunteers, R2* of renal medulla was higher than that of renal cortex (P<0.05). Compared with those of volunteers, medulla R2*s in patients with CKD were significantly lower [(16.40 ± 2.47)/s vs (18.17± 2.38)/s, P<0.05]. There were no differences in cortical R2*s among CKD stages and volunteers (P>0.05). However, medullar R2*s were lower in patients with CKD1 [(16.55 ± 2.12)/s], CKD4 [(16.48 ± 2.95)/s], or CKD5 [(13.99 ± 2.21)/s] than those in volunteers [(18.17± 2.38)/s] (P<0.05). Conclusions: BOLD MRI is sensitive to renal medullary hypoxia, and which is helpful for diagnosing early stage of CKD.