Objective: To prospectively evaluate the feasibility of diffusion-weighted (DW) magnetic resonance (MR) imaging in the assessment of renal function in patients with chronic kidney disease (CKD).
Methods: Seventy-two healthy volunteers and 43 patients underwent coronal echo-planar DW MR imaging of the kidneys with a single breath-hold time of 16 s. The patients were grouped according to five stages as indicated by the K/DOQI CKD (kidney disease outcome quality initiative). The apparent diffusion coefficient (ADC) value of the kidneys was calculated with high b values (b = 500 s/mm(2)). The ADC values were compared between patients and healthy volunteers, and among different stages. For statistical analysis, Student's t tests, ANOVA, Pearson's correlation tests, and Spearman's correlation tests were used.
Results: No difference between the cortex and medulla could be observed on DW images of all volunteers. Patients with CKD had significantly lower renal ADC (t = -4.383, P = 0.000) than volunteers. The ADC values of kidneys were significantly lower than normal at most stages of CKD, except CKD1. There was a negative correlation between the ADCs and serum creatinine (sCr) level (P = 0.000) amongst the patients.
Conclusion: Diffusion-weighted MR imaging is feasible in the assessment of renal function, especially in the detection of early stage renal failure of CKD.