Combination of renal apparent diffusion coefficient and renal parenchymal volume for better assessment of split renal function in chronic kidney disease.

Objective: To investigate the value of the combination of the split renal apparent diffusion coefficient (ADC) and renal parenchyma volume (RPV) by diffusion-weighted imaging (DWI) for assessment of split renal function in patients with chronic kidney disease (CKD).

Methods: Forty-eight eligible participants (36 CKD patients and 12 healthy individuals) were included in the study. All of them underwent DWI (b = 0 and 800 s/mm) examination with a 1.5 T MRI scanner to determine the split renal ADC and RPV. Glomerular filtration rate (GFR) was measured by 99Tcm-DTPA scintigraphy using Gates' method and used as the reference standard. All statistical tests were performed using SPSS 20.0 and MedCalc 10.0 statistical software packages.

Results: Split renal ADC, RPV, and their product were significantly correlated with GFR (γ = 0.493, p < 0.0001; γ = 0.337, p = 0.018; γ = 0.708, p < 0.0001, respectively). The product of split renal ADC and RPV had a significantly higher correlation with GFR (γ = 0.708) than split renal ADC (p = 0.0002) and RPV (p = 0.016). ROC curve analysis showed that the product of split renal ADC and RPV was a significantly better indicator of reduced split renal function (AUC = 0.893) compared to split renal ADC (p = 0.0455) and RPV (p = 0.0326).

Conclusion: The combination of split renal ADC and RPV obtained by DWI can significantly improve the assessment of split renal function in CKD patients.