Study on blood oxygen level-dependent magnetic resonance imaging for the assessment of early renal hypoxia in chronic kidney disease

Abstract

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.

Keywords

• |chronic kidney disease|blood oxygen level-dependent magnetic resonance imaging|hypoxia